I agree with Photoart. "Eneloop batteries manufacturer will always advise you to use eneloop chargers, GP batteries manufacturer will always ask you to use GP chargers and energizer batteries manufacturer will always ask you to use energizer chargers.That's the way they make money."
Not a manufacturer recommend any other brand to be used!
There is a very good Nimh charger in the market " Powerex MH-C800S Eight Cell Smart Charger ", came to know about only recently. They never advertise anywhere! This is about $60 (US), bit expensive than other brands in the market when compare. Most important fact in this particular charger is, it charges all batteries loaded individually. Not only that it conditions Nimh cells and discharging facility is also there. I went thru many feedbacks and all are positive, positive and positive! ( I have ordered one and awaiting ) Since most of us are using Speedlights [on camera hot shoe type] with Digital SLRs, usage of Nimh AA size batteries are common. Spending little more on a charger like this might be a wise investment.