Oooooooooo......The age old question! (We need the mods to add a poll onto this thread.)
I've only owned the ISM Ex., so I can't honestly give you a non-biased opinion. The ISM was absolutely stunning. The paint app. was gorgeous. The issue I had with mine is that everytime I received one from Sideshow it was chipped! I loved the piece, but couldn't live with the chips, so now I'm ISM-less. I still want to find a mint replacment though, but that's going to be the challenge and you might find yourself in a similar situation if you go with this piece. Furthermore, since the ISM Exclusive is out of stock, I would NOT settle for the regular. I would definitely go for the Exclusive on this particular piece. It's the only way to go IMO. It changes the piece dramatically with those few additions to the base.
However, with that being said, I think I was more hyped for the Back in Black than I was the ISM during PO and processing times. The Back in Black Spidey is more of the Spidey I know. It looks sleek and just says, "I am awesome."
I don't think you'll have to worry about chips on this one either. I also feel that the base on the BiB has "one up" on its ISM counterpart. The Scorpion's tail, Goblin Glider shard, and Doc. Ock. tentacle speak "louder" than the Capt. shield and Iron Man mask, IN MY OPINION. I'm sure some with disagree though.
Bottomline: If I were in your situation, I would go with the BiB Spidey. Even though I hope to get both eventually, if I had to chose only one for now, Back In Black Spider-Man wins in my book. (Congrats on the new marriage BTW! If she's doing this for you, she sounds like a keeper IMO.
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