I got some 2650mAh Duracell NiMH's from Office Max this weekend for $12.99us.
Are you paying more for the precharged? Honestly I don't think there's any added value to precharged. It seems like NiMH's lose about their entire charge after sitting for a month, and it only takes 15 minutes to charge them up.
LSD (
Low Self Discharge) show many advantages for the correct application.
For example many on CPF have more than one flashlight - and usually they (all?) have batteries in them ready for use.
With regular NiMH rechargeable batteries (like the ones you just bought) after about 2-3 months they would be flat, or have very little charge left for any real practical use.
Whereas the LSD batteries like the Duracell Pre-Charged would likely still have well over 85% the charge (that's actually about the rating for the level at 6 months to 1 year).
So the maintenance is much lower for LSD's - it is probably advisable to check and charge them maybe once every 6 months (eg: like when the clocks go back or forward - when one changes the batteries for fire/smoke alarms).
15 minute charging is convenient and works well -
however as many have found it can be rather harsh on the batteries and can very occassionally severely shorten the life of them.
Anyway in a power outage - one canNOT charge those batteries.
LSD batteries combine the ability to retain their charge for a reasonably long time, and the economy of rechargeablity.
The crossover point is after about one month where the LSDs show advantage over a regular >=2500mAh NiMH.
Kodak Pre-Charged are
@$7.88 4pk from WalMart
RayOVac Hybrids are $8.97/4 also from WalMart.
eneloops (the most well known and popular) can be found for less than $10/4 (see also
Eneloops now at Costco!)