Living in the High desert, I ride on the track (and street) in temps from the low 30s (winter months in the morning) up to the 110s. Personally, I would never buy a nonperfed suit. In temps 60 and above the perfs are awesome and welcome (and in the 90-110s pretty much necessary). Even with perfs I'm sweating when riding on the track when it's in the 60s.
For the winter mornings where the temps start out in the 30s and rise to low 60s in the day, I start out with a very thin windbreaker on underneath in the morning and in a couple hours it comes off. The front of the legs on my suit are perfed also, so on the really chilly mornings I sometimes throw on a tight thin pair of wind pants....but not too often.
So, after all that rambling...My vote is absolutely perfed.