Since I don't use Google Maps on my G1, I can't help you in that regard, but switching to anything but 1.6 is not a good option. I have tries almost all mods all the way up to 2.2; the main processor and gpu in G1 are just not capable of handling anything above 1.6 very well. Sure, 2.2 looks pretty on G1 but I would rather have a responsive phone than a good looking brick.