The 7000 doesn't allow correct video overlay playback with video acceleration enabled. (This affects daphne).
As for the rest, I've got 2 7000 based cards and 1 9000 (I thought it was 9200 based actually) avgas and in mame and I don't really notice a difference.
There was alot of complaining when the 9200 came out about the scrolling being off by a couple of hz or something like that, you would have to check the archives to find that.
Later,
dabone