Their just being smart, use common sense on hills. To get back to your question on performance and longevity. If the specs on any new tractor/zero turn says it will do this or that, just figure that you will need a little more then they say. They used to build overkill into things back in the day, but today things are built with just enough to get the job done and with no overkill. Most manufactures don't want their stuff to last a lifetime because you won't be back to buy another in a few years. If you go with a hydro make sure you get one that has a filter and one that you can change the hydro fluid. Keep the cooling fins and cooling fan clear of dirt, grease and stuff. You can make your zero turn/tractor much safer on hills by putting ballast in you tires. Ballast will help with traction also. Keep us posted on which way you go, there are some on this forum that will give you the strait info without all the smart azz remarks. I have to admit I've got a smart mouth on me at times. "But thats just me"