in more related news, this elitist ---tallywhacker--- got his hands on the jxd s7300 and I'm not impressed with it either. 
Can you tell us fps for PSX, N64, SNES... ?
MAME4droid, any glitching or sound crackling?
psx runs fine with the one game i tested. n64 worked great too, haven't tested snes.
their pre-packaged version of mame4droid runs fine too. Unfortunately, the mame4droid from the play store did not want to scan the sd card for roms no matter what i tried.
As for android games, vice city, and jet set radio were arguably the two biggest games i tried which did not run at all. Setting up games to run using the controls wasn't that difficult but unfortunately the app used to set your control scheme for each game can cause games to crash or go back to the main menu making it very difficult to set them up properly.
Overall the twin sticks feel grainy and the setup involved to configure your controls on average is just overbearing, a bit worse than setting up a dingux emu that doesn't have a built in file selector.