As I keep testing these, mGBA is clearly the superior emulator. emGBA has bells & whistles, but it does not stand up to mGBA when it comes to performance, It isn't close. Something has changed on the emGBA emulator recently. It has never performed like the official, but the latest versions are not much better than VBAgx or WiiMednefen as for performance. What a shame.
Interesting, I didn't know this. I've been using emGBA thinking the performance was the same in the two emulators, but after trying Crazy Taxi: Catch a Ride in both, I can confirm it performs better in mGBA. That means I'll be using mGBA from now on, even though I'll be missing the filter that emulates the way colours are displayed in an original GBA screen.
Just a follow up regarding my own test results. Testing around 30 "Heavy" games using mGBA 0.8.4 stretch screen 0.9-0.9, bilinear smooth filter, results were outstanding. Testing the same games with latest emGBA, results were as follows... MotoRacer - 59.4 - 60 mGBA - 51 emGBA Payback - 56 - 58 mGBA - 48 - 51 emGBA Super Monkey Ball Jr - 54 - 57 mGBA - 47 - 50 emGBA Top Gear - 59 - 60 mGBA - 52 - 53 emGBA Ultimate Winter Games - 59 - 60 mGBA - 54 emGBA V-Rally 3 - 60 mGBA - 53 - 57 emGBA I had minimal settings for emGBA during tests & it did well on plenty games. I do like what the emulator has to offer and appreciate what the developer has done. It is possible I'm missing something, but regardless the settings I throw at emGBA, the frame rate isn't affected. It sure does look great.