The scary stuff about hybrid battery replacement has turned out to be largely urban legend. My son drives an Escape hybrid with over 160,000 miles on the original battery with no decline in performance. Prius batteries routinely go 200,000+ and can be reconditioned for as little as $1500, far cheaper than a set of diesel injectors. But I will admit that hybrids may not fare so well in the RV world. The key to the long battery life is the controller maintaining a state of charge between a fairly narrow range. For more power on long pulls you may have to draw the battery down much more, resulting in shorter battery life.