A few months ago I switched my route to take advantage of the MUP that is about 0.2 miles from my house. It's going a little out of the way, but I just did the best estimation I have yet on Google maps (which doesn't let me map routes on the MUP) and was surprised to find that the difference is only about 0.3 mi. I thought it was more about 1 mile.

I didn't think I'd like the new route more because it was longer and also involves more riding on a highway, but being on the MUP and not having to stress about cars has trumped everything else and then some.