US2k for the win.
It has many more applications, it looks way cooler, only a few things can do the same effect. It is easy to use, easy to hide, almost angle sensitive, and can enhance everysingle trick by a notch.
The gecko, the effect although good, I find is a annoying product. They raise your hopes on something that you think is totally new and awesome, but when you get it, youre like.... "oh... this....dammit..." It is a good gimmick, but its not a new original product. There are so many gimmicks out their similiar to this that its not even funny. The only difference is this can vanish heavy and large objects, while some other products cant. Angles are a tad annoying, sound can be annoying as well.
Both products have clothes requirements. Both cost a hell load. Both can do great effects. But the US2K can be adapted to do alot more.