This is quite funny... Bruce, why do we seem not to agree on so many things?
Though I suppose there have been threads where we agreed!
My experience of all electric roasters (and I've tried a few) is that they are always sensitive to line voltage. You can normally work around it, provided things are stable, but if there are fluctuations then there are bound to be effects. Even the boss man agrees with this
here
I seem to remember that the Behmor was designed specifically to combat this, and you can certainly configure it dependent on voltage. I've still noticed considerable differences depending on where it was plugged in, in my house.
I'm really liking this roasting idea, even if it is more than a little bonkers. I'd be a little concerned that people would want to try a freshly roasted espresso, which might not be a good idea. However, just showing people how
fresh coffee blooms in a FP is likely to be an eye opening experience for most!