I'd pick Rock, or Normal. I find setting up a Sandstorm/ Stealth Rock combination (with Tyrranitar) quite devastating, especially with a swift, hard-hitting Kabutops (EV trained). My team would be:
-Tyrranitar
-Kabutops
-Armaldo
-Aggron (Mega)
-Rhydon
-Tyrantrum
Unstoppable...
Although I did...