I agree LiFePo4 is alot better but a rental
-Gets knocked around alot
-Probably will get run dead flat regularly
-Will be exposed to alot of theft hazard
LiFePo4 aren't exactly the most forgiving batteries and they are much much much much more expensive. Especially as a trial. I'm not sure Id want to give someone who has no experience with them and no investment in their condition a set of LiFePo4 batteries. Particularly as an aftermarket kit where the batteries often aren't bolted securely to the frame and well protected.