We stayed 6 nights in the room of Melissa & Nicole and everything was just perfect!
They gave as a very warm welcome when we arrived in the late evening and were so nice and helpful to us during all the days.
Also the room was absolutely perfect for our days in San Francisco. It's big enough for 2 persons including luggage and very clean and modern. It has everything you may need (TV, microwave, fridge, coffee machine,...) and such a comfortable bed! :)
The neighborhood is very nice, Noe Valley is really a lovely district - quiet, nice colorful houses and clean streets and has also some very good bars and restaurants around the 24th street. Although it's a residential area, it is central and has good connections via public transport to downtown SF and other districts.

If you go to San Francisco, take the room of Melissa & Nicole for your stay - it will be the best decision! ;)