I bought a replacement battery from GreenTec in Fall of 2012. Using GreenTec’s video, I was able to replace it myself fairly easily. Unfortunately, by Summer of 2013, it was failing – unable to hold a charge – turning on warning lights – and sometimes shutting down. GreenTec honored my warranty – and then some … This Fall, they personally delivered another battery to my house and replaced it for me. Over 500 miles on this battery and running fine.