I tried roasting my own beans once and it was a ton of work and made a lot of smoke. I just buy 5 lbs at a time from a place on the internet which roasts when I order and ships the same day. It tastes great and I don't have to deal with roasting.
A project like this is fun if you also enjoy the tinkering, but given the markup on roasted beans, spending money on an appliance is very economical.
If you go through a pound of coffee a week (which is likely for two adult coffee lovers), that means you'd have to spend almost an hour per week to roast your own coffee using the Behmor.
It just depends on what "economical" means to you, I suppose. One hour per week roasting/managing is significant to me. If I could find a place that would sell me just-roasted beans in 5lb or more bags, it might be worth it. I paid $300 for the Behmor and I pay about $8-$10 per pound shipped for green coffee. If you said, "Scott - here are some great tasting beans that we'll roast for you right before we ship them, and they are $12 per pound", I would sell my Behmor. At this point I've learned most of what I'll learn about roasting coffee - now it's just a matter of spending that hour a week. If I could pay a company $2 per week to reclaim that hour though...