I haven't had time to stop and give this a proper review since getting it a couple of days ago, but wow this thing is awesome!! First impression - it is huge! I looked through countless pictures prior to ordering this in an effort to get a grasp on the overall size of this figure, but pics don't quite seem to do it justice. It's a tall one for sure, but that's what I like about it! The paint job is incredible and proportions blow the 1/6th version out of the water (and I'm still a fan of the 1/6th).
This may seem minor but the one thing that I am particularly impressed with is the shoulder pads. You can maneuver the arms however you want and still adjust the shoulder pads so that there aren't gaps like the 1/6th. I have to say, this really is some fine work by Hot Toys. I'll post some pictures soon when I have a bit of time.
One final thought, and I'm excited about this - it has not ruined my 1/6th IM figures for me. I was very fearful that I would no longer like the 1/6ths after marveling over this quarter scale (and the 1/4th is leaps and bounds cooler), but I really do still love staring at the other IM figures in my collection. No immediate plans to sell my 1/6ths anytime soon, but I'm sure acquiring more 1/4ths is on the horizon!