My main thoughts here are that its hard enough to control the temp of the beans with gas heat, which you can control preciously and immediately, and you can see what's happening with the flame. Don't get me wrong, its very doable, but it takes some effort and concentration. That said, I couldn't imagine trying to be precise enough to control a profile to my desires with burners like you find on a stove top. When you set a stove at "8," it takes a while for it to get there. And likewise when you turn it back down to "2." And while this change from 8 to 2 is happening, you don't know where the element is in the change. No bueno for coffee roasting.
In short, I think the buyer will be able to learn this machine good enough to produce decent coffee, but control over the roast will be very limited. You get what you pay for at ~$2,200, but I think this roaster would leave most people I've met at GCBC wanting for more control, and perhaps more power.
Oh, and when I was looking for a roaster, I researched this one. I found stories of people having fire problems. Scared me off.