It's alot of fun, but it does fail to capture the magic that made the first Red Faction so very memorable.
Thankfully, Guerrilla isn't that kind of hack job. It's basically Far Cry 2 where you trade in the first person view and an attempt at combat realism for a 3rd person sci-fi aracde-y feel. It's alot of fun, and the element of destruction through the entire world is what really sucks you back into playing this game when you should stop and take care of your day to day responsibilities.
Unfortunately the story doesn't live up to the original and neither does the overall atmosphere.
As pretty as it is, it lacks that sense of foreboding and tension that made Red Faction 1 the silent clone competitor to Half Life 1. It's a real shame because if those elements were captured, this would have been a phenomenal gaming experience.
But as it stands, it's alot of dumb fun while your interest lasts, and it will occupy a pleasant spot in your gamer memory afterwards, but it's unlikely to inspire you to play it again and again like a Red Faction 1, or a Half Life, or.... etc.
Oh, and while it may not be a hardcore challenge for the hardcore gamer, "dumb fun" doesn't mean dumb-ass design. There is a basic level of skill required to play this game.