for me its teh toss. i find terran too clumzy and my APM is definitely not my strong point. zerg is quite fun to play but my muta control is way too crap. despite reading 134123 articles on how to control them i still cant make them efficient.
i rely on surprise attacks and tactics to win games. toss just wins it for me. HT,DA,arbiters omg my favourite units in the game are all in toss. i also enjoy rushing and toss's powerful early game compliments that.