I stayed at the Prague Marriott and had a great experience too. I was upgraded to a suite. The CL was great and well stocked. In addition the lounge contains a few PC's with connectivity. The concierge was very good as was housekeeping. One thing, if you are arriving by train, call the hotel ahead of time and arrange to have their limousine service pick you up. I made the mistake of using a metered taxi and was, well, taken for a ride. On the return to the station I used the limo and the price was half (about $25 if I recall).

After Prague I checked into the Vienna Marriott. Although the overall property was nice, it wasn't "really" nice. It's an older hotel in the Marriott system and is in need of updating. The lounge was satisfactory and breakfast can be taken in the lounge or the hotel restaurant. The location of this hotel is great, right on the Ring and a block away from the central shopping promenade.