I stayed at the Vienna House Munich Westpark for two visits of three days each in July and was very satisfied with my stay. The beds were firm and comfortable; the rooms were quiet and convenient; and the rate was far less expensive than for most other Munich hotels I'd seen, particularly with such high ratings.
I chose the Vienna House because of the high satisfaction ratings, relatively modest price, and the fact that it boasted a fitness center. Upon arrival by public transport, I had some hesitation-- the hotel is near the Harras stop, and so not particularly central. It is not a charming neighborhood, and almost directly across the street from not one but two discount adult video stores. As a solo woman traveller, I was a bit concerned about the safety of the neighborhood, but I had no trouble whatsoever. In addition, just behind the hotel is a Lidl grocery, a small but nice chain bakery and a very large pharmacy, so it's extremely convenient for budget travellers. The breakfast buffet was fantastic, but the Lidl was handy for purchasing bottles of water and chocolate bars; and the pharmacy for shampoo and the like. It is within walking distance of WestPark, which was fantastic, and I walked to the park and back every day.
The fitness center is tiny. It has two inexpensive stationary bikes, neither of which were well-maintained, and I believe one elliptical trainer, perhaps one treadmill (or perhaps two elliptical machines). There was almost never anyone else using the equipment, but the machines themselves did not work well and there is not much to choose from. On the other hand, the windows are large and you can open them for plenty of fresh air; and there is a room filled with chaise lounges beside the fitness machines (this could be done away with in order to increase the number of machines), and a very nice sauna which I used once.
The staff was outstanding and probably what I enjoyed most about the hotel. I would absolutely stay again if I return to Munich.