First things first... the hotel room I had was fantastic. The bed was very comfortable. The room was incredibly spacious, with 3 TVs, a sunken "living room" and a comfy couch. There was a separate bath and shower as part of a very large bathroom. The maid service was very friendly and did a great job.
The rest of the property was pretty good. There was no sportsbook (not allowed in Missouri, sadly), and the casino was nice enough, albeit somewhat stingy. I really liked the setup, where you could enter the hotel without having to pass through the casino. I enjoyed the concourse that allowed you to walk by the restaurants and bars on your way to the casino (or the conference center).
Parking was plentiful, the hotel/casino is close to "historic St. Charles" and very easy to get to, especially from the airport.
The only downside was the smoking... which was allowed pretty much everywhere outside the hotel. But that's par for the course with casinos.