Oudie or Garmin or both for a airplane & glider pilot?

Hello all,

I'm a power pilot transitioning to soaring. Before I starting flying
gliders this summer I was on the verge of purchasing a Garmin 500 GPS
for navigation in rental airplanes. Now that I'm starting to gain a
little more experience in soaring, I've noticed that many of the more
experienced pilots have PDA/GPS systems that they use for cross-
country soaring. A good "turn-key" solution for soaring seems to be
the Oudie. If I was going to solely fly gliders I would just buy the
Oudie, I'm wondering whether any power pilots out there use the Oudie
as there backup navigation source, and whether they find it to be
adequate.

Best,

Terence Wilson