OK, given that eneloops work significantly better the first time (longer life, more light during that life) and cost 6x as much as cheap alkalines (a 4 pack of eneloops costs $10, with a 4 pack of name-brand alkalines being about $4 and a cheap pack about $2 (but we'll assume a sale and bring that down to $1.50) and assuming that you already have a charger, the eneloops only need to work six times without significant degradation to beat the alkalines -- anything after that is gravy.

And in my ample experience with them, they work at least many dozens of times without any noticeable reductions in capacity or capabilities. The manufacturers claim hundreds of cycles, and I have no reason to doubt these figures.

I don't keep track of the number of cycles on my loose cells like I do the battery packs I use for my R/C planes, but I've bought a bunch of eneloops and clones (perhaps 40 cells?) for all my gadgets, lights, toys, controllers, etc., starting a few years ago, and I have not noticed any reductions in capacity, and only one cell has failed (and that was due to accidental abuse rather than any failure with the cell.)

And before that I had regular NiMH cells, and indeed many of them have since worn out over the years -- but it did take years and probably hundreds of cycles. But now I only buy the low self discharge rate batteries (like the eneloops) -- they're better and only cost a little more.

You aren't really trying to argue that alkalines are cheaper than rechargeables in the long run, are you?