Just to be clear, do you folks have the edge or forerunner?
I have had no problems with my forerunner 305 (knock on wood), but I only have about 2,000 miles on it.
As far as signal acquisition, I turn on my forerunner 305 when I'm coming out of the parking garage at work in the evening, rather than waiting for it to get a fix (which takes forever in the concrete jungle where I work). Although it will sometimes take as long as a mile to get a lock, it doesn't throw off the resulting trace except for making it shorter.