I have an F80 with Nikkor 50mm f1.8 and 28-105mm and love the system. If you go that route I would recommend those lenses wholeheartedly. The 28-105 is a really lovely zoom to use and the 50mm is a diamond-cutter!

However, for street photography it is less than ideal. Even with the little 50mm on it, if you wave an SLR around people notice you. I don't have a rangefinder myself but, for this application, I think it's the way to go.