I guess you're mostly looking for batteries that perform as well as the label says they will. Especially the somethingFire batteries tend to have grossly overrated capacities. That doesnt make them bad quality batteries per se, but if you expect to get 2600 mAh out of them, you're going to be disappointed.
The could just be honest and label them 2000 mAh or something, but i guess thats not very good for marketing.