Just wanted to share my experience with bitlocker. I have the following specs:
i7 860 (quad core)
NVIDIA geforce gtx 580
My computer never had hang ups or issues until i started using bitlocker. Microsoft word crashed 4 times in a row when trying to save a file. But, it had *never* crashed in the year I've owned my computer. And multiple programs had issues with file access after it was turned on, so unless you have very sensitive data I would say don't use it!
~uninstalling bitlocker (which takes hours and hours) as I type ...