My girlfriend and I usually look there first before we look at hotels.
I've used it in Chicago, Traverse City MI, Los Angeles, Santa Rosa CA, and probably a few more I can't remember right now.

I always make sure it is a private residence with our own separate entrance. The only negative experience was in Santa Rosa because the place smelled like weed and we don't smoke. We just wanted to make sure that the owner didn't try and charge us for it.