Peter asked what was my thinking behind the shape of the stir arm attachments so here is an attempt to explain: The arm that goes up the side a bit was intended to bring the beans down if they tended to pile up at the edges. Actually, it does that pretty well. The other arm that is horizontal was to give some randomness to the agitation; it angles in or out depending on the rotation direction. Actually, the first times I used it, the beans moved very well but I did one pound roasts then. Since I have cut down to ten ounce roasts the stir rods tend to push the beans around in a clump so I removed the horizontal rod. The temp probe actually pushes the beans out of the clumps when ever the mass gets around to it so I keep thinking having a stationary or even counter-rotating rod would be beneficial; stationary would obviously be much easier. All that being said, once the beans get advanced somewhat in the roasting they become larger and lighter at which point the agitation works well. Even though the beans get pushed around in somewhat of a mass, my roasts have all been very even so I'm not sure it is a significant problem. I guess I am so interested in getting the Turbo Crazy to work as well as I can is I don't want to waste any more of my good coffee. :-( David.