I've beaten DW a few times on NES. This was the first time I beat the GB version. Best change from the NES version is not having to open the menu to walk up/down stairs, talk, search, or open chests. I played it on the Super Game Boy, and the borders around the Game Boy screen are pretty neat, a nifty addition. Very short (took me about 6-8 hrs), but considering the time it was released, I'm not complaining.
People seem to complain about having to grind a lot in the DQ games, but I only grinded twice (once at the very beginning to afford a weapon and armor (about a half dozen battles), and once to buy Magic Armor (probably around 15-20 battles (ran into a few Goldmen, which sped things up significantly))).
7/10