[ahefner]

Not Neo Geo, but I was fascinated with Galaga a while ago and alternated between using MAME on Linux and MiSTer, and it definitely felt better on MiSTer. No stutters in frame rate, felt slightly more responsive, probably a little less latency on the audio. Didn't make a huge difference given my lousy playing, but it was interesting to compare them back to back.

Also, although the above is probably not the best case scenario comparison on the software side (MAME on an underpowered laptop), having written an emulator myself (not necessarily a great one), and particularly going through a convenient portability layer like SDL, there's just a lot of code between you and the hardware, which itself isn't representative of what you're emulating - for instance, sound and video are running at different clock rates and will drift apart, whereas on real hardware there's a single oscillator driving everything, so you have to jump through hoops to adapt the sound to the video rate, and latency creeps in.