Good quality NiMH will last a few thousand cycles.
http://www.ultrasmartcharger.com/phpBB3/viewtopic.php?f=5&t=91
Not to mention their LiPo-based solution is inferior: they state a 1560mAh capacity @1.5V for their AA battery. A good and modern NiMh AA battery will have close to 3000mAh @1.3V-1.4V.
(Also note that to get 1.5V output from a LiPo cell they are using a step-down converter with obviously not 100% efficiency, efficiency will inevitably depend on power draw as well, and it's probably noisy, which a NiMh battery won't be...)
Besides:
- The required added electronics makes it inherently less reliable than a simple NiMh battery (connector, charging circuit, protection circuit - hoping they included one - and step-down converter...)
- They state 1000+ cycles: I seriously doubt it.
- They state that a NiMh battery takes 9 hours to charge: not with fast chargers that are widely available. A NiMh battery doesn't take much more time to charge than a LiPo battery with these and even when fast charged, they will still survive more charge cycles.
- I wouldn't trust the thing safety-wise. I didn't see any mention of compliance to any UL standard or anything in that vein. And I don't know where they get their LiPo cells from. (Edit: I saw they show a test report for IEC 62133. That's something. The posted header doesn't show any clear reference for the tested product though, so I don't know.)
- And as already said, the product has already existed for years.