Bugaboo is absolutely correct. Hero is much better in pretty much every aspect - character creation, mechanics, supplemental quality, you name it. Simply put, Hero is just more fun than d20, and that's not just an opinion. Pretty much everyone I know who has tried both games agrees. Heck, my friend Trent donated all of his d20 stuff - over $650 worth! - to the local children's hospital burn ward after I ran him through a Hero adventure one weekend in January. With results like that, I'd say that the choice is clear. Up with Hero, down with Dee-Two-Zero!