We have been running a walker 48" ghs with 21hp kubota gas engine for 5 years now and ready for its sixth. Now has 2800 hrs on it and as far as repairs go, we had to replace the gears in the gear driven deck once because it wouldn't mow over 10" stump (covered in leaves, oops). Replaces all belts, most you can change w/o tools in only a couple of minutes. Still trying to think if we really have had to do much else to it becides new blades, filters, etc. I still consider our walker to be our staple machine in our lineup it just does so many things well. Many of our friends run them also, their results mimic mine, well thoughtout machine. The new HD gear drive on the GHS decks share the same internals of the new 74" deck. It will be a lot quieter and stronger than the current standard model. If considering a new walker I would definitly spend the extra $250 -300 for it. I feel my walker still has another 2500 or 3000 hrs in it with little effort, so it might deserve an upgrade.