I went the 178mm route since I saw a lot of people here on the forum with that setup. I'm not trying to be the fastest or anything, I just wanted a nice bump for enjoyment purposes. Also, I am holding off for now on any additional cooling upgrades. I also live in a warm climate most of the year here in Florida, so that's another consideration of mine. The 185 from what I have read produces more heat than the 178, which from what I'm told will necessitate a super cooler even more than with the 178.

I don't know the hp difference between 178 and 185mm pulleys with a proper tune, so I can't comment on it.