I've tried a few of the OGL d20 games, and this is easily the best one. The key to the approach is rules simplicity. The rules are there to support the GM but not get in his/her way. The addition of knacks -- a sort of free-form advantage derived from actual gameplay experience instead of voluminous lists of feats -- is pure genius. Only here do your characters truly get better at exactly what they do because they actually did it (instead of because it helped to kill something). Plus, each knack has a story behind it, making it fun to recount how you acquired this one or that one. And isn't that why we play these games?

Give this game a try -- you won't be sorry!