Query on Geo Pilot GPS

I just got the AvShop.com weekly flier spam and noticed an old portable GPS
I had looked at a while back. Nice color and Victor Airways, but seemed to
be directed at the Euro Market so I passed it up.
Now the new Geo Pilot claims Weather with just an "antenna option". Anyone
have experience with this model, likes & misses? Most importantly, what's
the detail on the weather option? Is it a built in XM reciever (aka 396) so
I only need an antenna, or do I need to buy the whole XM reciever-antenna
box and interface it (aka the PDA)?

http://avshop.com/product/2974/5 for reference.