You can read the whole article and its references by following the related link below. However, this is the outcome.

If you are in the market for rechargeable batteries, there is very little difference in performance. The life of the batteries is claimed to be 2x by one manufacturer but the article did not have a long run test to verify they would outlast competitors by that amount. By the way, that is the number of recharge cycles, not how many hours they will run a device.

Average prices:

PowerGenix Batteries: $11
PowerGenix Charger Bundle: $23

Energizer Batteries: $12
Energizer Charger Bundle: $20

Eneloop Batteries: $10
Eneloop Charger Bundle: $21

As the article said, a safe bet is whichever is on special.