I just did a ham and monitored it relatively close over the 12 hour cook. I had an digital probe in the oven and stemmed oven thermometer in the smoke hole they were as close has you could see.
At an average temperature of 225 with swings of plus or minus 30 degrees it takes pretty much forever to get to an internal temperature of 190. Personally, I think something in my Smokette is defective, but I don't know if it is the setting dial pot, or the actual thermostat in the oven, but this problem does limit my enjoyment of my CS. I suppose I should call customer service, but I normally forget until I have something in the smoker.
On the other hand with the digital controls on my old restaurant 105 once it comes to temperature and evens out it probably holds within plus or minus 5-10 degrees, during the whole cook and hold cycle.