If you want good Ys III chip tunes, listen to the PC-88 version.
fixed that for you.
Anyway, the scrolling is fine. People have this misconception that smooth scrolling is some sort of required thing. The parallax in Ys III is fine. The sprites are running smooth. Everything is playable.
The game plays good. The choppy ones play good too.
The MSX2 one is pretty awesome, for example. I'd say overall, the MSX2 and PCE ones are the better versions to play. The MD one might be if Adol wasn't retarded looking.
To say the game runs like shit makes me wonder if you even played it, as the scrolling that people complain about isn't even present for large portions of the game.