Hi, I have two sets of Konoc batts (1 set= 4pcs of 2500mAh) and a charger. So far they have not failed me when used with the SB-800 Speedlight - fired many shots until I lost count. Full charge for 4 batts takes about 20mins (claimed 15mins) and they don seem to overheat. The construction of the charger looks flimsy though. Comes wif car and usb charger somemore. Think I bought it for under $40. Varta is abt $80, and it comes wif a huge voltage adaptor, cumbersome for travelling... Not sure how long my Konocs will last, but so far so good.