The Sanyo charger I got with the eneloops is 560mAh for 4 batteries 1120 for 2. That is quit aggressive. A charge at 200 mAh is better. Also it charges 2 or 4 batteries in pairs. But not all devices use even number of batteries. Canon GP-E2 uses 1 AA, my small flashlight uses 1 AAA, another uses 3xAAA, so does few of the remotes. So how do you charge 3 batteries? You wait for a fourth. But that not a pair. One pulls a battery from a device when it do not supply the necessary juice. The demand of a motorized tooth brash is not the same as remote. So a charger that charge only pair will stop when the first of the two is at capacity leaving the other at less the full capacity or, worse, continue, causing overheat in the first battery to charge to capacity until its pair reaches that mark.
A high end charger charges each battery individually! It also allows you to choose slow or fast charge if necessary. If you keep two simple chargers (a slow one and a fast one) beware, the "pairs" can be different (1+2, 3+4 or 1+3, 2+4) so do not "pair" different kind (AA/AAA, low/high capacity etc)