Anyone can use this machine. Some may not want to.
Positive Product Points
EZ to use (fire and forget) low smoke and odor relatively quiet consistent, even roast
Negative Product Points
fire and forget (no control) long roast times relatively small roast volume 5min programmed cool down is not sufficient
I decided on the Z&D for several reasons (based on reviews here): low smoke, easy of use and volume/cost. I got all thos things. There is not much smoke. If I run it with the discharge pointed towards the vent fan set on low the smoke detectors don't go off and in a while you can't tell I roasted at all. It is a very easy machine to use. You plug it in, set the time, and press start. There is no temperature changing, no variation minute by minute. There are only a few parts: the hinged top, 2 gaskets, one screen, and the roast chamber. The book says thay are machine washable but I wash them by hand in a few minutes (and I hate doing dishes). The auger does a good job of keeping the beans moving for a even roast. I don't measure my green means with a scale so I can't say with certainty how much I am roasting but I get about 16 fl oz out of a roast. There are 2 lines on the roasting chamber: 'fill' and 'dark roast'. I fill to fill every time. There are some who preheat the machine be plugging it in a hitting start with no beans in it. Then unplug it to stop it, add beans, and roast. I've tried this and found it helped a little in getting a richer roast in less time but I'm fairly patient.
There are down sides to simplicity: simplicity (that whole freedom to and freedom from thing). There is one "roast curve" and Zach and Dani set it. Those wanting to get the perfect roast out of every bean will not want this machine. As I said above, roasts can be kind of long. My decaf beans get set for 21 min (last 5 min is for cool down), regular beans 27 or so. Like I said, i'm fairly patient. And, also as I said before, I get about 16 fluid ounces from a batch. I also only drink about one moka pot a day. I roasted 5 times to get through Thanksgiving just for me, me sis and HER for the weekend (48oz a day, give or take). I also find the cool down cycle to leave the beans still hot. I just take them out when after one minute of programmed cooling (I tell myself this is for the heating element and such to cool; this many be silly) and put the beans in a collander and cool them off outside (its already in the 30's daily).
Anyone can use this machine. Some may not want to. I'll keep it as it was a gift I asked for and it does what I need.
Gift. I don't even know where it came from.
Three Month Followup
I have found a few things that make this machine better. One was suggested in the forum of using a piece of paper board (cereal box) as a hot air recirculation. The heater takes air in on one side and discharges on the other. By putting this cardboard over the discharge and sending it back in the roasts go a little faster. I now roast in about 16 minutes or so with 145g of decaf and 120g of regular. I try to roast both in the same day, one right after the other. This way the decaf roasts in about 17 min and then the regular roasts about 15 min. I find I have pretty good control over the degree of roast now, too. Although, I usually roast just into second crack as I use a collander to cool rather than use the programmed cool down. I so far (over the winter and now into April) can cool the beans in a couple minutes. For my rate of coffee use and degree of involvment I care to put into coffee roasting (I still might try stove top roasting) I think the Z&D is the right machine for me.
I did not, however, change any of my original ratings.