The Energizer battery packs have 1200mAh capacity each. Eneloop Pros have 2550mAh capacity per battery (so I think it would be 5100mAh total 4.25x the capacity of the packs. Does anyone know if that's how two batteries drain?). I have been buying eneloops for close to 10 years. I have only had two batteries wear out. I highly highly recommend the starter pack for anyone looking to get started with them. Be aware, some knockoffs exist!
Starter kit 10AA, 4AAA & Charger (not PRO) $41.99
Eneloop PRO 4AA w/Charger $26.30
If you get really serious about your rechargeable batteries, I highly recommend this charger as an upgrade.