For the first two days, I stayed at a more expensive downtown resort, then checked into this Govt run wonder. The difference was palpable. If there was a race, Peterhof would have beaten the other hotel hollow.
Peterhof is old colonial building with SPACIOUS rooms and elegant bathrooms. The entire building has maintained the charm of the Raj. It is moderately priced, so you can opt for higher grade rooms. It is away from the crowd (the mall is good 20 minutes walk). Food was edible though they took eternity to serve the food.
My suggestion:
If you are driving down to Shimla, look no further, book into Hotel Peterhof. If you are not driving down, moving to town etc might be a pain from Peterhof. If you are into Raj and elegance attached, rush to Hotel Peterhof