You can't really compare the pandora and the Wiz, as they're in entirely different categories. YES the pandora IS better than the wiz. YES it can run 3D games, and has all the features the wiz has and more! BUT, it's also much larger, it costs more, etc. Really, when you come down to it, they're impossible to compare. The Pandora is more of a full-featured linux mini-laptop with a touchscreen than it is a gaming system, and the Wiz is a mini gaming system with a ton of 2D power and a little 3D power that has yet to be fully exploited. But no, it probably won't run Quake 3 or battle for wesnoth, and even PSX is a little out of the question at this point. But what it should do is serve the purpose of being a fairly small system that's able to emulate NES, SNES, GENESIS, MAME, etc. at full speed, or VERY CLOSE TO full speed, and if it can pull those things off it's definitely worth it.
Honestly, though, if I could go back and stop myself from buying one just yet, I would. $180 US is a tad on the expensive side for a device like this.