1)  Great cooling cycle - the beans come out nice and cool.
2)  You can customize your roast profile.
3)  Good roast size.
4)  I like the attachment to hook up to a dryer vent.  I've tried it with a powered vent fan, which helps suck all the smoke out.
5)  Relatively easy to hear the cracks.

1)  You can't turn the fan off and on to hear some of the quieter cracks.
2)  You have to re-program the roast profile every time you unplug the machine (which is every time if you roast outside like I do).  With flash memory so cheap, this seems weird.
3)  Questionable build quality - the cover keeps popping off during cool cycles.
4)  The thermometer is worthless.  It doesn't measure bean (or chamber) temp, so why bother?  Put that money into flash memory and more profile storage.
5)  Why on earth are the time increments 1 second?  It takes forever to cycle through all 15 minutes.
6)  Roasting decaf is tough, since there's no chaff to block airflow.

Overall, I'm pretty happy with this unit.  Compared to my POS Rostos that broke after only a few roasts each (or simply arrived broken to save me the effort), I've had good luck.  I wish it were a bit easier to program (e.g., 1 second time increments is crazy), given that you have to reprogram it every time you plug it in.

Customer service is great.  I had my chaff cover break, and a new one arrived in the mail quickly.  Compare this with my Rosto.  The fourth one broke 2 years ago, and Steve Glovin still isn't returning e-mails.

I've not seen the over-roasting problems others describe.  Perhaps I don't have quite enough amperage, or perhaps my model has a good heater.  If anything, I have to use higher temperatures than Tom at Sweet Maria's describes.

Sweet Maria's is amazing, as always.