Yes I think not having them fixed is better (for me) as they move forward when you turn the bars full lock and therefore don't restrict your movement. If they were fixed they could not move.
Heated grips. Most are not very good. Its the controllers that fail due to not being properly watertight. I have heard the symtech (spelling?) are the best. They going on the bars and grips are put over the top.

__________________
check out www.redbikejohn.com for all the latest race reports from the CHEC and enduroland.