Lifetime generally means either lifetime of the ORIGINAL OWNER or life of the company (Please do not ask I actually work .. sort of,,, for a company that changed it's name to get out of lifetime contracts... ).
And yes, all warranties are limited, Attach a hand grenade to it, pull the pin and run like blazes.. NOT COVERED... (Ok so I'm being a bit...er.. extreme but you get the idea I hope).
Someone talked about thise EMS/Surge guard units and autoformers.
Though both offer some level of SPIKE supression.. they do completly differnet jobs. Neither is a sub for the other. You need both With the EMS/Surge guard between the autoformer and your RV.