It is pretty good. I bought it yesterday. I didn't play it today, but from the few hours I spent with it yesterday, there seems to be the potential for a ton of customization.
I'll admit though, the dialogue is a bit stale, but you're not exactly playing this game for Square-Enix storyline/plot. Even though "Save the princess!" is considered a cliche, lately, RPG devs have gone to such extreme lengths to try at creating stories that try to stray so far from cliches, they end up with a story that is too complex/confusing/absurd/unrelatable/etc. to enjoy. So Nightmare of Druaga is a breath of fresh air in that respect.
The game reminds me a lot of...
I really liked Brandish on SNES. I don't know how many games there are in the series, but that's the only one I've played. It seems the others never made overseas. I'd really like to play them. =(