My newest model is, I believe, a 750 but not the RV model. I can't make any judgement about the RV760. My disappointment is with the Garmins that I own. They seem to have no ability to distinguish more or less desirable routes except by allowing interstate or non-interstate preference and they do route around cities that are not your destination.
The latest bad experience was in route to Petersburg COE park north of Augusta, where we planned to stay for the Masters. It took me off of I-20 at exit 175. Next thing I knew it was trying to get me onto a dirt road. I stopped and pulled out my Rand McNally and realized I should have gone on to exit 183 with a straight shot to my destination. This was a little longer but no dirt roads.
Maybe the newer models are better than the one I have.