hopefully mfm understands your question. we're talking about Eneloop AA's, right? here is kreisler's contribution summarized in a nutshell after having studied the subject on CPF plus my own experience confirming it:
+ Eneloops are cheap. Check ebay, 1 cell costs 1.70€. other brands purchased from a local small retailer are more expensive! so dont be worried about price/loss of money or eventual aging effects after 10yrs of use!
+ Eneloops are no-brainers. they dont age (if you have C9000 to do a forming charge called "Break-In"), and you dont have to take special care of them. whatever and how often you do with them, no problem. other cells would age because of a user's abuse, Eneloops dont. if there is an Eneloop flying around in your house and you dont know its charge status (100%, 60%, 20%, whatever) -- and this is the case with most users in the world because only few possess a DMM or C9000 or BC-700 -- then just use it (until depletion) or recharge it. this decision will not affect the Eneloop's life or age or quality. Eneloops are robust, keep their charge, and they are designed to be used this way: as no-brainers. Just trust Sanyo/Panasonic and the 1.70€ which you once paid for it!! -- And once you learned to trust this no-brainer procedure, using Eneloops will turn into joy and green and happiness, instead of worrying about aging, cellulite and whatnot.
+ have you read the info in this thread, incl. the PDF-specs sheet for Eneloops and discharge graphs? you'll learn that the Eneloops like "high flow rates" .. at least they dont harm them. call a C9000 technician and ask him/her about charge and discharge rates and he/she will answer "Eneloop or not, choose 0.5C charge rate and 0.25C discharge rate; since Eneloop 2000mAh are the most common rechargeables nowadays the C9000 is already pre-programmed that way. i.e. 1.0A charge rate (yes, this high!) and -0.5A discharge rate", see also the official C9000 FAQ's on the Maha website.
+ the 1000mA/-500mA is a common accepted and agreed upon "standard" on cpf. if you believe in the power and wisdom of cpf, then you need to believe this outcome/result/finding: 1000mA/-500mA --- simply adopt it, and forget about your doubt, worries or questions
+ there is no proof or long-term study which proves that deviation from this 0.5C/-0.25C rule for Eneloops results in better quality Eneloops (i.e. less aged cells). in fact, Eneloops are only a few years old, and even early adopters of Eneloops report that after years of use and abuse their Eneloops (which they had never taken special care of) are still like new. pretty much unaged. this holds true especially after mfm's mentioned forming charge with a proper machine (e.g. the C9000).
In summary, Eneloops are simply awesome. Charge or recharge them anytime, dont care about topping off or the current charge status, and they will last you for several years to come. No special care needed. You can even discharge them to full depletion (that's what i do in my hundreds of runtime tests. you know my BLF reviews!), no problem whatsoever. With other NiMH cells that would be a problem, with Eneloops it isnt anymore. Eneloops are really really special in every respect. And cost only 1.70€ per cell!
Okay, cpf also recommends that you get a C9000 and play with the cells (e.g. doing the Break-In every 6 months or so, and analyzing the cell's effective capacity once per month or so -- to be certain that they really havent aged haha) but Eneloops can live with Sanyo/panasonic chargers equally well .. because they are no-brainers.
Hope this helps. You got a nice charger!! :)