+1 to the recommendations of getting eneloops and a good charger. Stop screwing around with cheapo shit like this play&charge kit and get a good set of batteries and a good charger, and basically stop thinking/worrying about battery problems forever.
I too use the BC700 charger. I bought it back when it was just the 700 and the 900, and the 900 was not only more expensive, it also came with a bunch of (useless to me) cheapo nimh AA cells and also had the potential overheating issue. Since I didn't want to pay for extra crappy non-LSD cells, and was wary of the overheating issue, I went with the cheaper BC700. The BC700 works fine for me anyway since like others I don't see the point/need of charging at very high currents. I charge my eneloops at 500ma and it works fine. If you really need high current/rapid charging cells then maybe get the BC1000 but otherwise it's mostly a waste.
IMHO the biggest benefit of a charger like the BC700 vs. a "regular" charger is the fact that each battery slot is a fully independent charging circuit. Most cheap chargers only charge batteries in pairs, and unless you have matched your cells previously, your batteries may not be getting optimum charge because it is paired with a different cell and the charger does not control each slot independently. A good charger will have independent voltage monitoring and charging for each battery you put in it, meaning every battery you put in is going to get its optimum charge.
The ability to measure the capacity of each cell is also a bonus because then you can actually find matched pairs of cells that are similar in capacity. I have a total of 16 AA and 8 AAA eneloops (use them for xbox controllers, headlamp, flashlight, LED lantern, camera flash, etc) and I have gone through and found the capacity of each and matched them up with each other to find the closest sets, both in pairs and sets of 4. Now honestly for Eneloops which are high quality cells to begin with, there should be very little variation between cells (I think all my AA cells came in at around 2100mah +/- 50mah) but if you happen to get a bad one or one that is significantly lower in capacity to another, then you can identify and isolate it.
Having a stock of high quality Eneloops and a good charger, I find the whole system works just great and I never have battery problems. Need more power? Just grab a fresh set off the shelf (I usually have 4-8 spare ready to go) and you're all set. I know they're charged and since they're LSD, they will be pretty much full even if I charged them months ago. I know when a cell or cell(s) are dying out. I also got like 100 free energizer lithium AAs from a friend so I have a crapton of those too. I use them in my wireless mice because the lithium AAs are much lighter. Also I will use the lithiums if using my stuff in cold weather because lithiums are the best for cold weather.
It's always satisfying when I use my batteries up and then put them in the charger, because even though they are being charged independently, they will each finish their charge cycles within a couple of minutes of each other. A variance of 3-4 minutes over a 240 minute charge cycle (~4h at 500ma) is excellent IMHO and shows that the cells I use in pairs are very closely matched. I see similar behavior even when I discharge/charge them in the BC700, they follow each other very closely, both in discharge and re-charge. Having well matched sets of cells means I am getting maximum energy from each cell because they die out at the same time relative to each other, rather than one going out and the other still having unused charge.
As for the newer Eneloop XXs, I'd say they may have benefits being used in a 360 controller if you game regularly/often. Assume if you go through a set of batteries in about a week- that is not enough time for self-discharge to really make a big impact on your battery capacity, so you may be better off with the higher capacity but slightly worse self discharge of the eneloop XXs. But if you only change once a month, then there isn't going to be much difference or benefit.
As for the "inaccurate" reporting of battery charge in the 360 controller, I notice this too with my eneloops, and suspect that is because the 360's battery level indicator is calibrated to alkalines as opposed to nimhs. Alkalines have a linear discharge curve where the voltage slowly drops from 1.5V (nominal at full) as it is used up. NiMH cells start at ~1.4V nominal for fully charged, quickly drop down to about 1.2V, and stay there right until the very end when there is a sharp dropoff. So the 360 may not register the battery as getting "low" until the very very end where the voltage has left the 1.2V plateau region and starts nosediving. That is why you see it report as "low battery" and then 10 minutes later it goes dead on you.
Ultimately it doesn't bother me though since I always have a fresh set of eneloops on the shelf
. Basically as soon as I see the flashing ring on the controller, I just swap out for a fresh pair.
Ruahrc
P.S. people say the Maha C9000 is slightly better as a charger (seems to terminate more reliably at low charge rates, can accept "deader" cells, etc) but I prefer the interface and usability of the Lacrosse chargers because you can see the stats for all 4 cells at once, rather than having to cycle through them one by one. Also I like the slightly more compact form factor of the Lacrosse charger.