I have to travel to Pittsburgh several times a year, and I always stay at this Residence Inn. Yes, it's a bit old and outdated compared to other Marriott properties I've stayed in, but it's very clean and perfectly fine for a long weekend. The staff is awesome -- I've never had a bad experience with anyone, and they are always willing to help in any way you need, whether it be something hotel-related (i.e. asking for extra towels, etc.) or needing directions to local attractions. The rooms are a good size and feature a nice kitchenette. Anytime I've stayed here, the bathrooms were clean as well. The only thing I really don't care for is their "business center", which is one extremely slow, 90s-era computer and a printer. There is free wi-fi too, but it's slow.
The location is not bad. It's obviously close to UPMC, and it's not far at all from the University of Pittsburgh or any Oakland attractions. It's very easy to get to the rest of the city by car -- I haven't found that anything worth seeing is more than a 15 or 20 minute drive. I will definitely continue to stay here.