Well to be honest the older sets were mor epowerful, but if you play like I: Which is using anycard you happen to have new or old, it really adds a lot to the game that you couldn't normally do, artifact decks became even better since Mirrodin.
But i fyou want to challenge one of my many deck PM me, and I'll get back to you as soon as I am able to.^^
Edit: OH yeah, I'm gonna attempt to enter one of hte bigger comps in the Salem Portland area over the summer, so I get into them I'll let you know and I'll bring a long my decks and challegne people with them, Most of my decks don't lose, they're almost completely invincible.