I am officially an idiot: I just checked to see whether a Samsung 40T 21700 battery would fit in the XTAR VP2, and it did. So I spent $54.95, plus shipping, on a great big charger I don't need. Oh well. I can tuck the Gyrfalcon away for later, I suppose. It charges a whole slew of batteries, so it could come in handy at some point. Or maybe I'll just try to sell it. I wish I could get into the Classifieds here.
Grumble.
1/11/19: After a decent night's sleep I am feeling less buyer's remorse today. It helps that I'm currently charging eight batteries at a pop, which is a wonderful luxury. Besides, it's not a bad idea to have a backup charger, right?
1/12/18: The charger I've been using for AAA batteries generously decided to give up the ghost yesterday, giving me yet another reason to feel better about the Gyrfalcon, which handles them beautifully.
I am coming around.