I'm not on Sprint, but my best friend is, he previously had the Pearl and had no reception issues, now with the Tour he says the reception is very spotty, specifically inside his house, where there was never an issue previously...
updating the PRL will do nothing, the tours shipped with 60652 which is the latest version... it's in your head, or it was something else that fixed your phone
if your coverage is truly bad, then I would call sprint and try to get an airave from them
that's not the issue....the issue is that some tours have this problem...some don't...and it's due to some type of update with the OS, and not the hardware itself