This Eneloops are madness, last forever and at full power. Well, I could try the remote controlled car with Juniors. So far I have always bought the expensive batteries "with the copper head". But they were also quite fast at the end and the car was getting slower and more feeble. With the Eneloops the fun lasts much longer and without derating. Use these batteries mitlerweile in any household and electronic equipment.
Use only Eneloops, with an original Sanyo charger (MQR06, microprocessor controlled), because the charging should not damage the battery. So do not use cheap charger - very important!