The Donatello is is a great location a block from Union Square, and about a 5-10 minute walk from the Powell st BART station. It's close to many things of interest.
For a hotel type room in San Francisco it's quite large. The staff are friendy and helpful.
However it is a timeshare, so rest assured they will try to get you to see the consierge desk for a welcome packet and a brief pitch on something.
Also, if you are on the East side of the hotel there's a loud nightclub across the street. You'll either want to be on a really high floor, or on the west side of the hotel. Otherwise it can get really loud.