ive heard the 510 batteries wont change on my blu pcc because the polarity is different. but how come the attys and cartos work? will they charge on my blu usb charger? i want to get a mega batt to use and use my blus for backups but i'll need a way to charge it. if i buy a mega batt and a charger i miight as well spend a little more and get a 510 kit :/