I used a popcorn popper for more than a year, and decided to 'step up' to a real roaster. I figured the air popper was the style I was used to, so why not try one built for the purpose? Turns out, it's pretty much as crappy as a cheap popper.
First problem, the canister is too small, so I can only roast 1/4 cup at a time. That's 10 batches every Saturday morning, or approximately an hour of walking in and out of the house swapping beans. Too much hassle.
When the machine is hot, you can't remove the canister from the machine because the base of the canister swells with heat. Don't force it, or you'll pull the glass tube out of the canister base like I did.
The top cover is too pieces that you pull apart to clear the bean husks. Be very careful with this pieces, as even dropping them to the table top will cause them to break. I break a piece off about once every two months, so my unit is looking pretty shabby by now (2 years so far).
The timer is hard to get precise, so you pretty much has to supervise the roasting process if you want to be consistent. It would be so nice to just set it and forget it, but you can easily be off my 30 seconds which is enough to turns a medium roast into a dark roast.
On the plus side, I've made a ton of great coffee with this unit.