Seems to be a decent conversion. Has all the cut scenes and levels, small load times, sprites roughly the same size as the arcade, and the music is straight from the Neo.
Negative aspects include loss of 2 player (although you can pick the alternate character at startup), scratchy and a few missing voices, and the removal of some eye candy. Enemies still scale into the foreground, only not as smoothly. Most of the nifty "smooshing" effects done on enemy sprites after they die are gone, instead they flash and disappear.
One thing I'm not sure of is if it had less on screen enemies at once than the Neo.
Ironically, the port is done by Sammy