I've stayed at both the Quality Inn and the Courtyard for CPE Nationals in previous years.
The Quality Inn is pretty basic and kind of run down (and this was a number of years ago). There is no elevator and bringing things up and down the stairs got pretty old pretty fast. The rooms did not have refrigerators standard in them and I only got one because I saw one coming out of another room and claimed it. I stayed there the first year that CPE Nationals were is Springfield because they were considered the "host hotel." I haven't been back.
The Courtyard is a very nice hotel. I've stayed there the past two times and have been happy both times. The staff is amazing - they couldn't have been friendlier or more helpful. However, it is a 5 story hotel and they have two (small) elevators. The staircase is not accessible from the interior of the hotel and there is no access from the exterior. It's not a deal-breaker for most people, but if you have a dog with "issues," this might be a consideration. When we were there last June, they mentioned that they were due to start a refurb of the rooms in November, but it doesn't appear that it happened.
I know that a LOT of CPE people stayed at the Red Roof and I didn't hear anything negative about them. Right now I have rooms booked at both the Courtyard and the Red Roof as I couldn't get a room with two beds at the Courtyard (right now I have one with a bed and a sofa bed). There are more food places immediately near the Red Roof than the Courtyard (although it is only a short distance to food from the Courtyard).
I hope that helps people! If you need more specific information, please let me know. With CPE Nationals having been in the area so frequently, I'm sure that I can find someone who knows the answer to just about any question.