Just got them today so i'm an Instant Expert. From what I've researched the main problem is when charging. Especially the first three times.The Hperion 1420i is pretty advanced and watches for overvoltage which is the main cause of fire. A full charge is 4.2 V/cell.I charged them to 90% capacity or around 4.13V. Another problem is over discharge. I Plan to stay above 30% until I get a Low voltage cutoff system that is ordered but not shipped. Some very serious people seem to think this charger solves the overcharge problems by allowing charges to slightly lower voltage. I have 10AH/12s and have ordered another 10aH/12s I don't know if I'll buy another LVC depend on how much trouble it'll be.