Better than buying Starbucks and cheaper than shipping from Vivace.
Positive Product Points
8oz (green) Batch Size - Larger than most air roasters Easy to use Produces Fresh Roasted Coffee No mechanical or electrical issues in 2 years
Negative Product Points
8oz (green) Batch Size - Finished batch size is about 6.5oz (Problem if you want to sell 1/2 pound bag)
Ambient Temperature Sensitive - I've got the controls that are supposed to account for this, however, roasting outside in the summer (90deg+) get to the 2nd crack in 17 minutes and in the Winter (50+-) I'm at 18.5 minutes. The coffee still gets roasted, but the 17 minutes is a much better result. If you want to try to reduce the ramp time, search the forum section for instructions by CraigA. I haven't tried it though.
Keep it CLEAN - Keep the reflective lid reflecting and the air flowing or you'll never evern get to the second crack. Again search the forum section for maintenance instruction by CraigA.
30 minute cool down required between batches
If you want to roast coffee for anyone but yourself and you don't want to spend over $1000, the Alpenrost and Hot Top are your best choices because of batch size. I've read a lot of about others who have experienced reliability issues with the Alpenrost. I've had mine 2 years with no issue as long as I keep it clean.
After about 6 months with no detail cleaning, my roasts were not making it to the second crack. I did some research and found that the reflective lid must remain shinny and blocked airflow will cut off the heater. You can remove the reflective lid with two screws and clean it in the sink. Be careful because the edges are sharp. I started doing this after every 8th batch. Airflow is another area that needs cleaning. Clean the lid after the reflective piece is removed. Also remove the top of the machine to clean around the fan housing and sides. The screws are located on the bottom. Remember where the long ones go (they hold the lid on) and two of the screws are under a rubber foot. I don't disconnect any wires to the control panel or remove the fiber board covering the thermal switch. I clean under the top housing once a month with a shop vac.
Roasts are better than what I could buy locally and I experienced good reliability. The Hot Top wasn't available when I purchased the Alpenrost. I'm not sure which I would buy today. Probably the Hot Top so I could get an 8oz finished batch.
Lot of discussion on maintenance and cleaning in the forum section so do a search if you are having problems.