Just to let you know: N80 with Wayfinder and a GPS Module (in my case the Nokia LD-3W (BT 2.0 but should work fine with BT 1.2 in our N80s)) drops the signal after about 30 s (it varies).
I called Wayfinder support yesterday and they say they are aware of the problem. They say it's a bluetooth bug in Nokia N80 and both Wayfinder and Nokia are working on a fix as soon as possible. But of course no time frame given still.