Jim,
I am beginning my thought process on buying a Ti-Tri. One of the first decisions is between the Sidewinder and the conventional cone. I would think the conventional design more efficient. True - or not? The sidewinder might be easier to feed. I don't know.
Now about the pot size? Mostly I would use it for the noon tea, but it would be nice to have one that could really cook as well. Do you expect the larger pots to be significantly less efficient for boiling a few cups of water (I use a BIG mug)?
Thanks for your time,
Jerry