I am a member of the EDC forum and this question was asked , one of the members recommended him to charge NiMH slowly as it will extend the life of the battery , is he correct ?
The general consensus seems to be that slower is better for the cell.
Our user Don confirmed that in this thread, and he knows a LOT about chemistry.
Thanks will pass the info on to the person who asked
That is not easy to answer.
NiMH cells are the most difficult charge properly.
For longest life, the cells should not get hot when charging.
Maybe you should tell us in numbers what you mean by slow...
Personally I think that .5C (^= 1A charge current for a 2Ah Battery) is ok for eneloops, but I wouldn't go higher on a regular basis. I had some 1600 mAh NiMH cells that lasted me for 10 years, and I always charged them with 700 mA.
Those old 100 mA chargers are way beyond outdated IMO.
Sorry I can't give you numbers as the person who asked the question wasn't specific he just wondered if there was a catch with the 1hr & 15min chargers as opposed to the 6 to 8hr chargers
1hr & 15min for a full charge is a little bit too fast for my taste.
15min is indeed way too fast, but 1 hour charge shouldn't be a big problem for high quality cells like Eneloops. Still, 2-3 hour charge should be preferred.
Kreisler's thread hits it on the head. Too much heat is bad for the cells. There's two ways to cook them - too high a current and overcharging/missing termination. Unfortunately charging to slow increases the chance of smart chargers missing termination signs and overcharging. Slower can actually be worse. There's a balance. I have seen some threads on CPF that very slow trickle rates can be effective. Quite possibly the rate is so slow that even a missed termination can't cook the cell much.
There's not a clear "slower is better" rule though because of the conflicting ways to cook the cell.
If too slow a rate is used, then the charger won't get as strong an indication from the battery that it is full and that can lead to overcharging. That would be less than 500mA for an AA battery. I think the sweet spot is 2-4 hours charging. The Sony charger I have uses a low charge rate (360mA), but it is actually pulsing a higher rate (1400mA). The higher rate gives the good signal from the battery.
Thanks i will pass on all your very helpful advice , and it has cleared up my choice of charger this the one I'm going for ,
Sanyo eneloop MQR06-E-4-3UTG
Best thing for me it can charge individual batteries
I change my charge and discharge rates every few cycles. Normally I charge my aa's at 1A and discharge at 500mA but every 4th or 5th cycle I do a 200mA charge and 1mA discharge.
I also break-in all of my new batteries which not everyone does. After a few months, if I notice certain cells not up to par (I have an excel spreadsheet keeping track of each battery 
) I'll do a refresh and analyze or a break-in. I know, I know......get a life right?
In my opinion yes and it goes for every battery not just nimh