Optiminer should be faster. Do not forget that you have to subtract 2.5% for the dev fee on Claymore while optiminer shows hash rates with dev fee subtracted already!
That's true, but Claymore has fan control! /sarcasm
I use AMD settings or GPU-Z. there is information about the temperature and fan.
as for me optimaler better than Claymore(my rig 7 gpu R9 390)