RE: Cheaper batteries, what have we learned?
Nice try Keith, probably the best comparison is $/flight as use habits will vary the parameters during life making comparisons difficult at best. Number of flights until batteries are unusable divided into cost is pretty definitive.
Unfortunately it takes a good deal of time to reach the end of life for most good batteries. I've generally observed "premium" packs available cost around $2.50/flt or less, that's generally 150+ cycles. That number has improved from around $4/flt a few years ago. It'll take a while for the performance of the current "new tech premium" packs to be determined - but prices are lower and expectations higher - time will tell. My experience with the "premium" packs is that preformance and reliability have continually improved with time to the present. "Last years" packs were excellent and the expectations for the current tech are even better. So overall a good value considering price & reliability.
My observations of the "low price" packs being used by others is that they are generally performing well, tend to be a bit heavier, and some are better than others. OTOH, these only need exceed 60 or so flights to be cost competitive. Just not enough info yet to reach any valid conclusion as to their long term value.
From my view there's more to value than just price - but that's me.