Yup Tucson is the perfect place for riding a motorized bike. I rode bicycles for many many years (Cannondale Raven, Gilmour tandem etc) and find the transition to a motorized bike to be a very easy one to deal with.
PS: Keep the reviews of the 4 strokes coming. I want to do the switch once we all can be sure of the reliability of the gear cases available for them. Lots of folks have them but not much in the way of reviews yet. I see one or two 4 strokes a week now, possibly the same bikes though.