I used a whirly pop for a period of about six months starting about six months into my HX ownership period.
I read up on technique, got a thermometer, and started making data charts of the temp profiles minute by minute.
Most of my results for espresso were ok, but not exciting.
I hit on a temp profile variation that produced a truly delicious cup, and I thought I had arrived.

I made the next batch striving to duplicate the roast from my carefully charted success pattern. The result? Bleech! A lousy batch - and I thought I was on the money. At that point discouragement set in.
I still have some greens in the fridge, and I will use them up perhaps with another run at espresso, perhaps for vacpot brewing. So far though, the difficultly of controlling the roast and the inconsistency offers less reward than I'd like considering the messy chore that it is, especially when you have to stand there and crank the thing...