Like everybody's suggested, I'd say TUMBLER as well. We're not sure if there'd be another relaunch, and it's getting scarcer by the minute, thus getting more expensive in the secondary market as we speak.
As long as Kato's alive, you're sure to get something tailored by him. Also, now that he's getting hired to provide the measurements and tailoring designs for some figures that are becoming mass-reproduced quite decently like in DX11 and as seen on the protos of Sideshow Joker, you might hold your horses for soon we might need not shell out huge sum of cash for a Kato suit, IMO. Another thing, 3rd party-made suits are becoming better in terms of quality and fit, for about 10% or less of the Kato price. My kitbash Wayne using a Mens Hommes Toy City suit on TTM 21 body gets enough attention from visitors. I think no one, unless a hardcore 1/6 afficionado, would say "oooooh KATO SUIT!" but everyone gasps each time they see the tumbler. Even those who have a tumbler smiles when they see another tumbler on display.