I used to like Gens because in general i thought it was a better emulator, now that Kega fusion has come out, the fact it sounds great, doesn't go back to windowed mode every time i try to open a rom, doesn't switch to 16bit every time i load it, with the filters too... I am converted.
..plus the high res of 1024x768 i can use and a ton of other features
C'mon, not using Kega for the intro effect, its not nearly as irritating as the auto 16bit switch-over when you load it, or changing back to windowed [if in full screen] when you try to load a rom.
Heres a shot of Knuckles Chaotix running, its running brilliantly, (fps is 50 because its a europe rom)