I think the fact that the game was so much harder than Zaxxon is what killed it, it's so hard I hear that the MAME team at first thought they screwed up the emulation because it was so difficult to play. Personally I prefer it over the original and wouldn't mind having one in my collection eventually.
It always kills me when videogame people complain that a game is "too hard"... The game isn't really that tough once you get used to the speed. After a couple weeks with it, i scored 45k the other night...