Roasting in an SR800 vs Oven, and a few tips
The SR800 fan motor failed noisily, so using the oven till it comes back from repair. We like a dark roast, both methods are working well for us.
Using the SR800: I offset the lid leaving a quarter inch air gap on one side for the chaff to escape, otherwise the chaff plugs the screen and there is no airflow. The chaff lands to one side within a couple feet, so put down an old towel first to make cleanup easy. The towel is first laid out on our stovetop burners (make sure no burner gets turned on accidentally!) and the hood fan turned on. Alternately take it outside and let the chaff blow where it may, but not if it's cold out. If ambient air is down around 60F the roaster may never get up to a temperature. Ambient air temps matter a lot, watch the beans and don't just try to time it. Beans double in size when cooking, keep that in mind when loading the roaster. I use max heat throughout the roast, start the roast with max fan speed. When the beans cook they get lighter and can fly up into the lid to escape, I reduce the air speed to where the beans are just getting stirred around sufficiently for an even roast, adjusting air speed 3 or 4 times during the roast. I bring the air speed back up during the cool down phase though that is probably not necessary.
Using the oven: I've only tried this a couple times now, this morning's roast went very well indeed. Preheat oven to 450F, lay the beans out in a large cookie sheet, enough to mostly cover the sheet but you don't want it more than one bean deep. Fitting two sheets in our oven can work, but know that different positions and sheet material can cause huge differences in how fast the beans roast, and multiple sheets can block the air flow. In our oven the heat was even enough that I only stirred the beans once, I also turned a pan 180 degrees when I noticed one side was cooking faster. My first attempt at oven roasting resulted in the majority of beans browned (not as dark as we like), other beans were black through and through, but with that mix the coffee tasted great. This moringing I was a little smarter about it and managed to have a very even roast. Have the fan in the stove hood running on high to exhaust the smoke to the outside, have doors and windows open when you open the oven as there will be a big boil of smoke rolling out. Take the cookie sheet outside quickly as smoke will be pouring off of it, use gloves and hot pads to protect your hands. Outside have a station set up with large metal salad serving bowls to quickly poor the beans into off of the hot cookie sheet so they don't continue cooking. Pour beans from bowl to bowl to cool them down, blowing to get rid of the chaff as you pour.
Conclusion: The SR800 is nice in that it is small and portable, efficient with power consumption, I can roast outside on a warm day, but temperature regulation is not ideal and with the cover on tight the airflow will be blocked by chaff. The oven seems to have better temperature control and can roast more,. Not having forced air flow inside the oven doesn't seem to be an issue, our propane oven has significant air flow for the flame, and I can see quite a bit of smoke rising up out of the back of the oven with the oven door closed, . Both systems take about the same amount of time, around 10 to 15 minutes for our very dark roast (not counting oven pre-heat time).
A countertop 4 slice toaster oven could be a good choice if the heat is even and well regulated. A cheap popcorn popper might well prove to do about as good a job as the SR800 for small batches. I haven't yet tried either of these devices. Like most, our stove hood fan expels the smoky air to the outdoors. If yours does not, expect a very smoky house.