Better than you're probably expecting.
Vandal Hearts is a great old-school strategy RPG. The graphics aren't the prettiest and the game isn't the most complex or refined you'll ever play. Some things about the game's mechanics are a bit odd--for example, you only have a set number of battles throughout the entire game, with six bonus battles if you can locate a set of items hidden on the various maps (and you only get once chance to find these items, because you only play on each map once). Thus, the game is inherently somewhat short (by RPG standards--it's about 15-25 hours depending on your pace). It takes a little getting used to.
However, Vandal Hearts has fantastic, fun characters and a great storyline. The battles themselves are full of colourful animations that really add to the game's atmosphere. The villains are a solid cast and the heroes provide a wide and entertaining cast, thrown into a fairly gripping storyline. I find myself playing four or five battles in a row, telling myself "I'll stop after the next one" just to enjoy the next battle. The first time through, this effect is even greater as you want to know what happens next in the story.
The battles themselves have a solid tactical system, where your different classes match up better against one another in specific ways. This leads to a very positing-heavy strategy game where the A.I. is pretty serviceable, and some of the maps are downright dastardly without being frustrating. The character class system is neat and it's fun to build up your favorite characters just to see what they look like as their next class.
I can only recommend picking it up if you can find it these days. It's a great, classic storyline wrapping around a solid combat engine to provide a fun experience you can spend some time on.