Okay, my FX (sn#10) is now only 6 months old and the stock battery died on me after only 40 hrs and will not hold a charge despite using one of the best recommended battery tenders - the same one which I used for my 2 previous Carbon Cubs. I had installed an AGM battery on my first Carbon Cub, and that worked great for 3 years, however, I don't recall the brand or model.

While I have seen numerous old postings about batteries, technology changes rapidly and I was looking for the latest recommendations prior to getting an Odyssey 680. Does anyone have any new recommendations? I fly in the Colorado area so high and low temperature extremes are the norm.