This is really just a placeholder to note that I replaced my GTN-650 with the GTN-650Xi to get the advantages of that updated model.
It's faster, the additional screen resolution is nice and the narrow hold bar on the bottom is welcome. The "Home" and "Direct To" keys are set just a bit lower than on the original 650 (not shown in image below).
The upgrade ultimately cost $2,731.41 (purchased new 650Xi for $10,200, trade-in original 650 for $7,500 less $31.41 shipping). Was it worth it? It's a subjective call of course. The additional resolution is appreciated as is the faster boot and response times.