Well, I ordered my new GPS. I got the BMW Navigator Adventure, which is the same as the Garmin Montana, but loaded with Motorcycle GPS Firmware, and loaded with North American maps. Price was the same as the Montana, and this model is intended for mounting to the F800 GSA.
Also, all of the Montana accessories work with this BMW Adventure model, so cradles and what not are ready available. The model I ordered is for the F800 GSA, but I cannot find any where online that states this includes the powered cradle. Not to worried though, as the Montana cradle is readily available for around $35. Touratech also makes a “locking” cradle for the Montana, and I just might get that as well for piece of mind.