I have the 55 cs. I have had problems with big temp swings since I got it in dec. 03. The temperture swings at that time was estimated to be about 100 deg. plus. I call cs service to resolve the issue---I got the run-a-round that this was normal. So they suggest that I check the temperture over 3 hr. So, I also conducted a test simalary to what ORICK did. The temperture swing was 100-306 degs. Cs told me this was normal and would average out to 225. However, the calculated average was 260 when set at 225. I really had to twist there arm to get a new thermostat. The 55 is working now. It looks like this is a problem that they have with reliaiblity using inexpensive thermostats. Overall I felt that I should have researced smokers more carefully --- I don't really be leave the smoke taste is the same as wood fire smoker's. To me ribs taste more steamed than smoked. You can actually wipe the accumlated smoke off the top of the meats you are cooking. When I ask cs about the red ring they said that after a 1 1/2 hour the meat will not absord anymore smoke and to get a red ring you had to us charcoal. Reading the forum, it looks like I am in the minornity .