We stayed for a week late July, and starting with the positives: the rooms are very well appointed and kept to a high standard. The rates are very affordable compared to western Europe. As all spa treatments are likewise affordable this makes a good value for money proposition.
The cons are, however, numerous: as most of the visiting populations is either German or Russian these (and Czech of course) are the prevalent languages, and only one of 5 receptionists spoke any useful English.
The food at the hotel (breakfast) is, as has been previously posted here, pretty bad and monotonous; the service gruffy. The service in general can be best described as amateurish if you're coming with expectations of a 4 star European or US hotel.
A good example of this is that we booked via the internet a suite for the week, and when we got there got a small double room. This was amended after 3 days (!) (When the English speaking receptionist was in to sort things out) and we were moved to a suite. Upon checkout it was a hassle getting the first three nights' rate lowered as the receptionist had to call the manager to get authorization (for a huge 30 Euro sum!), the manager first saying that we shouldn't get a reduction because we received free massages (which we didn't) and only after arguing at length did they deign to charge us the right amount.
All in all, a so-so experience. From what we saw in this town there's a gulf between the standards at the bigger 5 star hotels (where English is spoken and the service is at a high level) and the 4 star ones which are more like 3 star hotels in WE/US.