Great location for downtown business travelers or tourists. The hotel itself has been modernized but still feels a bit dated like so many of the buildings in Downtown Cleveland. I see this authenticity as a plus although I could see where travelers accustomed to generic brand new buildings might not fully appreciate the history in a place like this.
Staff was very friendly and helpful. Check-in was quick and easy. Breakfast was standard for the Marriott chain, which is actually pretty good.
Another poster said the parking lot was scary. It is not scary in a personal saftey sense but more in an "oh crap, I should've gotten the rental insurance" sense. You can find garages just like this all over New York and I'm sure there are a few more around Cleveland. Just make sure you get a small car or, since there's so much within walking distance and ample public transit, just forego the car and take a taxi or shuttle to/from the airport.
Overall, I thought this was a great hotel.
BTW, if you *want* to see a scary garage, head to the parking garage two blocks west of this hotel (I think - it's caddy corner from 45 Prospect). Take a ride in the elevator-of-doom, then pick a floor and wander around. See how many potholes and broken down 20-year old video surveillance cameras covered in cobwebs you can count. Enjoy the urine/ammonia combo wafting through the air. Then find the stairs (because the elevator has probably broken down again by now anyway) - the ones that say 'Emergency Exit Only'. Go all the way down to the first floor exit and walk out. It's a scene straight from Escape From New York. Enjoy.