I'll start. Spoilers obviously, but I won't use tags as I'll assume everyone reading this either has the set or want to know details. I was going to wait until I listened to everything, but as I'm listening to one album at a time multiple times over before moving onto the next, that might take a while, so I will post things as I review them, and edit this post as I have more to say.
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Packaging: Here are my pictures on Facebook. I will update that album as I get the other versions (vinyl, test pressing). It comes in a nice box with custom Styrofoam insert, so it will be easy to store if you choose not to display it for some reason. The accordion is spot on realistic looking! A few people who didn't know it was a box set thought it was a real accordion. It is "Yankovic" brand and a emblem that says "WAY Moby". The booklet is strapped onto the back, and there are snaps which you can undo to leave it open or keep it closed. Each fold in the bellows holds a different album. For the CD version it's full size artwork, folded over and glued, with the CD in a pocket on the back. The fronts are the album covers and the backs are pretty much the album backs though a few elements were moved around here and there to make room for the CDs. The artwork looks like it was designed so it can be reused for the vinyl. Where the pocket is could be cut out to show the label. The only minor complaint is that the artwork on the back of "Medium Rarities" is upside down!

Booklet: 124 page full color booklet loaded with tons of pictures! There's not too much text, a foreword by Al and a sentence or two on each of the songs on "Medium Rarities" and some thanks and photo credits. There's a chapter for each album and it lists basic info about each song, when and where it was recorded, who the musicians were, etc. -- basically info that what was or should have been in the liner notes on the original . Tedious to read, but great for reference. The pictures are grouped by album, and then there's a free-for-all section at the end. The focus is mostly insider and behind the scenes photos, which is really nice as most of them were new to me, but on the later albums there are some concert shots thrown in. I already told a couple of close personal friends with photos that their name appears in the booklet, but I'll let the others discover for themselves! Quite a few on this forum! Excited to put some names to the pictures, so please share which photos are yours!
Test pressing set: I'm not sure what I was expecting but they are kind of boring actually. White labels in plain paper white sleeves and that's it. Each one has a sticker on it telling which album is which and some numeric code underneath the name. Each album is also signed by Al, which is nice. I guess I was just expecting more, like a COA or something. It comes in a plain white box, with "Test Pressing" printed on it. It's supposed to be numbered (limited to 27) but I can't find a number anywhere. The albums were shipped in bubble wrap, so the white sleeves all got bent. On top of that I only got 14 albums, the missing album being "Medium Rarities". Also the booklet was missing. I've emailed customer support about the issues, but haven't heard back yet.

T-shirt: As far as Al shirts go, this one isn't too bad. The design looks better on the shirt than on paper. It's a baseball style shirt, which I don't really like to wear, but I probably will anyway. Hopefully they offer the design on regular t-shirts at some point.
Magnetic Dress Up: It's okay. The magnet looks to be pretty thick so I'm not sure how well it would layer. Also there appears to a lot of white space around each cut-out, which means your mix-and-match Al's will look stupid. Limited mix-and-match options as well. There was a lot of leftover white space they could have utilized to fit a few more outfits or props in, or at least a second set of pants! The one pair of pants they provide is intended to be re-used for the AP and SLN outfits, but since the number of Al heads is equal to the number of shirts/outfits, the comfortable thing to do is make as many Al's as possible, which means one of them doesn't have any legs!
Socks: These are actually really cool! I wish they would offer them separately for purchase. I'd buy one pair for every day of the week! Al's face is on the toe area. The polka dots are colorful and they should match any outfit. There's a subtle joke on the cardboard holding them together -- "Greatest Knits I and II" -- Nice! Whoever's doing merchandise for the upcoming tour, take note! We want socks!
Turntable mat: The mat is colorful and looks like it would be fun to spin. It's got a bunch of polka dots and dancing Al's on it. I need to dust off the record player and see how it spins.
Felt Pennant: It's felt and it's a pennant. Not too much more to say about it. Would make a nice wall hanging.
Medium Rarities: The first thing I imported into my music collection was this CD. I-tunes didn't recognize the CD so I had to manually enter all the details. Not a big deal since I usually customize the info for any CD I import anyway as I have a specific naming convention I like to use, so only a minor inconvenience for me, but I guess that could be annoying to some. I really hope my car recognizes it - haven't tried yet -- as that's a pain to update each track name manually in the car! First song I put on was "Beat On The Brat" and fell in love instantly! I know the pool of Al's cover songs is small, but this is easily my favorite cover song he's done! So catchy and I find myself going back to listen to it over and over! "Happy Birthday (New Version)" was the second song I listened to and coincidentally my second favorite on the album! It's kind of funny that there are 4 released versions of "Happy Birthday" now. Al's like George Lucas with this song, he will just keep updating until he gets it exactly how he wants it!

"Weird Al" Yankovic: After "Medium Rarities" I decided I would listen to the CDs in order, giving each album a few listens. I'm not an audiophile by any means. Of course I want the best sounding recording of any song in my collection, but I didn't necessarily buy the box set for that reason. But WOW!, to my untrained ear, does this album sound AMAZING! Whoever took the time to update these songs gets huge kudos from me if I ever meet them! I didn't know I needed better sounding songs until I heard them! Now I'm afraid I can never listen to the original albums again! The original first album is so raw and different than the others, but the updated album sounds so much more clean! I'm not quite sure how to explain it, but it just works so much better now! A few standouts to me were "Gotta Boogie", "The Check's In The Mail", and "I'll Be Mellow When I'm Dead".
"Weird Al" Yankovic In 3-D: Listening to these albums is like listening to all new songs, but all new songs that I know the words and music to. You just can't help hearing more with the new updated sound. They are really getting me in the mood for the new tour! "Midnight Star" sounds amazing, I think I'm falling in love with this song. I can't wait to hear it done live on the new tour! I can't help singing along to the last four songs on the album ("King Of Suede", "That Boy Could Dance", "Theme From Rocky XIII", and "Nature Trail To Hell"). The new sound gives "That Boy Could Dance" a whole new appreciation, and "Nature Trail To Hell" stands out as maybe the best on the album. The piano note at the end just seems like it holds forever now. I also wonder who will be the first to record and leak "Satan Eats Cheez Whiz" in its HD glory!
Dare To Be Stupid: I've already commented how wonderful these albums sound compared to the originals so no need to again. "I Want A New Duck" (HD quacks!) and "Yoda" deserve to be mentioned from the first half of the album. And while the first half of the album is one of my all time favorite album sides (think cassettes here people!), I think the last half really benefitted the most from the remastering. "George Of The Jungle", "Slime Creatures From Outer Space", "This Is the Life" and "Cable TV" were most noticeable to me. A strong album to start with only made stronger by the remastering.
Polka Party!: Climbing up the corporate ladder....
11/22: Added review for bonus items. Vinyl arrived.
Dave