Keith - I hear what you are saying. Most of my batteries last 4+ years and some I have are around 6 - 7 years old. I did have a batch about 3 years back which began to fail at 1 yr. After a bit of a row they went back and the replacements are working fine - so some batteries a better than others. I could go on using them longer but the hassle with batteries going down during a shoot isn't worth it. Having to stop a shoot to change batteries up the big towers just isn't worth it. To have a bank of 24 smart chargers might be difficult to justify. Maybe if I get a 'smart' charger and give each one treat in turn then that could work - or I don't bother and spend a little more time shooting - tough call??
