I have both as well.
In term of pose it's a personal choice - IS is more unique while IA is museum, i honestly like both equally. The pose i really do not like is the XM version, i know a lot of people love it, but to me it just looks very awkward with 1 shoulder hunched up. IA does come with 2 sets of arms for 2 different poses, IS does not.
In term of detail and paint, IA hands down. Both are top notch, but if you look at it closely IA's weathering, paint app and the way they layered the armor to create that 3d effect is the best i have seen in any iron man. And the helmet/chin/arc reactor is perfect (always a pet peeve of mine, very annoying when the head doesn't come out perfectly with aligned chin, clean black lines, or eye socket/arc reactor doesn't fit 100% with little gaps, IA doesn't have any of those issues).
Thank you for a great and detailed post. I struggled with this a bit, and I agree the IA is more polished, but in the end the pose on the IS version is just killer, and the quality is still probably the best out there after IA. So I just bought one from a fellow collector and it should arrive Friday. Looking forward to seeing it in the flesh
congrats you will not be disappointed with either one! i am just happy we now have different ironman choices to pick and choose from, it used to be only the ss version with the bad chin or the tight jean version.
agree with your assessment. While the SS versions are nice, and I almost bought the MK42 on eBay because I liked the pose, after doing some diligence I realized the paint apps were a serious QC issue. Plus the IS and IA versions have far superior paint with a nice shine to the finish vs the matte finish on the SS version. In any case, all this competition is great for collectors, forces all the manufacturers to step up their game!