I stayed here one night last summer following IRROPS (paid out of pocket). Was there for about 24h from 7pm-4pm. Most notable part of the stay was being driven from MUC to the hotel in 11 minutes by a mad taxi driver on a Tesla doing 237km/h (we had a kid in the middle seat and we were frozen with fear).
Location is terrible with the exception of being closer to the Lufthansa Express and being within 15 mins walk to Englischer Garden which we enjoyed in the summer. As mentioned, there's a U-bahn stop a few minutes walk away but getting anywhere interesting in town involved a change.
We weren't told anything about a lounge. Perhaps the benefit was discontinued. Did get the two drinks from the fridge. Also got the upgrade to the family suite and 4pm checkout.
Breakfast was good. Didn't check out the gym. It just felt like an out of the way cookie cutter Marriott. Fine, but nothing special.