Internal vs external GPS 
In my opinion the internal GPS of the Nokia N95 is sufficient to find a geocache. I found a lot of caches using CacheTrack and the internal GPS.
Today I was curious if I would really feel a difference when I am using an external GPS (my good old Holux GR230). It wasn't a scientific test setup. I just used the internal one for the first half of an multi cache and the second half was done using the Holux.
There clearly was a difference (as expected) regarding the accuracy. On the other hand the Holux' time to first fix was really long compared to the nearly "instant on" N95 AGPS. Also the Holux was a lot more sensitive for sudden turns while carrying it in my pocket.
In the end I came to the conclusion that the internal GPS is really sufficient for just finding geocaches.
But for getting most exact waypoints for my own caches I will use my external one.
Maybe I will replace my moldy GR230 with something more modern. I guess that would really make a difference in terms of receiving quality at bad conditions.
So if you worry about buying an external GPS just for getting started with geocaching: You don't really need it to find your fist (and a lot more) caches.
