Frodo has nasty compatibility, though I'd not say no to a Wiz version if it was easy to do. With some fiddlling around VICE is fantastic - I only wish it was a bit faster to load when true drive emulation is turned on (use command line to change the true drive emulation type and it'll run fast during game play even if it loads slow).
I'd reccomend that anyone seriously wanting a c64 emulator devote their time to trying to speed up VICE - the ability to play some of the great demo's that rely on disk acess would be fantastic.
EDIT - I should say, I still use Frodo on my GP32, now if only my GP32 had the power of my Wiz and it's trouchscreen it'd be THE best handheld in the world - I love the little joystick on my GP32.