I have been using the BC-6 for 2 years without any problems. I started out with 3s 2100mAh packs and am now up to 5s 4000 packs, so I've slowly reached my max with it. When I do have a question on programing/setup, a quick call to Evan at RC Accessory gets it handled. I will be thinking of upgrading to the BC-8, although I thoroughly enjoy the AC/DC capabilities which I can't do with the BC-8.............[8D]