just bought it,
it looks really good for a 12 year old doom alike and controls well.
$10 download, game has 40 levels, online play and such.
and when you die you can choose spot at which point you'd like to respawn(kind of casual approach I guess), but it works and you don't have to get back to your last save point every time(and it's pretty easy to die on medium difficulty).
excellent game, just as I remembered it.
definitely worth buying ^^