Any but popular ones here are PowerEx 2700, PowerEx Imedion and Sanyo Eneloop. The 2700 has more capacity while the imedion and eneloop has low discharge rate - meaning you can charge today and keep it for a year and there will still be charge in the batt. I think the capacity is only 2100.
I have, mostly PowerEx2700 and a couple sets of Imedions solely for backup.