I use the highly-coveted
West Bend The Poppery (not Poppery 2) and have used it since I began roasting 3 years ago

No modifcations. I roast only SM beans and only organic. I roast to 2nd crack always, which gives me a FC+ roast and perfect beans everytime!
I was using a cleaned can with bottom cut out the bottom to direct air and chaff, but found it wasn't necessary. I now pop without the top or butter measurer on and the chaff blows up through the top nicely (I let it blow around my rosebushes and roast on the front porch. Perfect). No beans escape or pop out ever. I stir frequently.
This popper achieves first crack within 4 minutes and second crack before the 5 minute mark. Subsequent roasts (I roast up to 4 batches at a time, at 1/3 cup green beans per roast) achieve a faster 2nd crack since the popper is already heated.
I LOVE this popper! I see one on ebay right now for $80 and am tempted to bid, but I only paid $35 for this one. They're apparently hard to find.
This is a solid, heavy machine and roasts PERFECTLY every single time.
I hosted a Front Porch Roast tonight in Indian. It's 50s, but perfect roasting weather with a breeze. I use 2 metal mesh collanders to immediately cool the beans, then dump from there on a cookie sheet.
I have roasted in our garage and basment, too in freezing weather. Keep this popper indoors so it doesn't freeze.
Love this popper/coffee roaster! I don't know if it was ever used prior as a popper but looked brand new when I bought it.