As others have said, the PCE ports are the best ones made back in the day. FF Special being the most impressive.
However, to be honest, these days those games are all super cheap for any system. The PS2 collections or even actual Neo carts might run you the same money...maybe even less, on a good day. Get them to see how great the PCE is, but if you just want to play Fatal Fury get the far superior PS2 collections which go all the way through Real Bout 2.