Well, depends how far you want to go back. Mame4droid Ver 37B5 is decent for the older roms (70s and 80s) and it runs these roms pretty flawlessly.
There is a newer version of Mame4Droid 139u1 which is compatible with newer arcade games (90s basically) but this version is very much more system intensive so not too much runs well.
Basically, if your looking at early arcade games to half decent stuff in the late 80s go with the first version. 2nd version really isnt that great I find.
However, Im yet to try Retroarch for arcade so others will have to chime in on that one.
Neo.Emu is also very good for the Neo Geo and that will fill up plenty of SD space if you allow it!