I owned a OS 160FX on a Sig Extra 18X6 Mej prop 13.5 lbs. It did not have unlimited verticle. Sure it would go straight and then fall off.
Did you own the OS 160 and test it or is it hear say?. I do not want to offend you but I do not think a 20+ lbs plane on a G-62 will have unlimited verticle. Unlimited to me is climb out of site and continue.