I received word from Aventon that Pace 500 1st generation battery is now available. I thought I needed a new one last spring but the problem was with the motor which solved the problem, but at the time, 6 months ago, there no batteries, only back order for this model. My bike is 5 years old, I have about 1600 miles on it...should I get one as a precaution while available? Its pricey - $499 - but mine still works well. How long can I expect the life to be?