Werker SLA batteries? (... better than PowerSonic?)

I am back to power sonic. Tried the Batteries Plus because of timing. First battery lasted less than a year before failure. They were great help etc. but the replacement battery failed again in the same timeframe. The previous battery was a Power Sonic I got with the glider. It was on the order of 7 years when it rapidly failed. One other note on Batteries Plus, the replacement battery doesnot get it's full one year warranty. The replacement battery only has a warranty of what's left of the original.

Still wondering if the charger is part of the issue, even though I was using the same charger on the old PS for several year.

Batteries Plus service and testing of the batteries was excellent. I just couldn't get them to work very long. Battery issues cause great uncertainty when flying way out from home.