I can attest after owning 1 Gear and 2 Hydro tractors here, the Hydro tractors offer a
considerable advantage in safety when operating on this extremely hilly and dangerous terrain. As for the 30%
slope preventing pickup of fluid, I can say I have operated on slopes close to twice that steep (close to 30
degrees which is about 57% slope) without any difficulty of fluid pickup in my Kubota L3400hst and my Kioti
DK35se.
Yeah, I have used my Kioti on slopes in the 50+% range, and had no problems with starving the HST. BUT.
When doing so, with the tractor pointed uphill, and using the backhoe, I CAN starve the implement pump.
This is noticable when extending the boom and dipper when, at a certain point, the sump gets low enough
to suck air. BTW, that kinda slope is steep enough to have trouble staying in the hoe seat. I was often a
little low of fluid when this happened. Not an issue, really.
My tractor score is now 11 HSTs and 5 gear-drive units, 4 purchased new. I wrenched on all of them,
including clutch replacements and HST rebuilds. For my use here in the mtns, I prefer HSTs by far,
but I do not plow fields. I find the HSTs much safer with my slopes, and most of the guys I sell my
tractors to are newbies who need a lot of guidance. It is not so easy to sell a gear-drive CUT around
here anymore, esp since 2008.
To the OP's question, I am very confident that HSTs are very reliable, and potentially more reliable
than foot-operated dry clutch gear tractors. Not hard to repair at all. If I got another gear-drive
tractor, I would get an electrically-controlled wet clutch unit, like Kubota's GST. The GST
requires very little use of the foot clutch.
Before I bought my 1st tractor (gear-drive Kubota), I labored under the delusion that the HSTs
were too much of a risk in terms of repair costs and unknown reliability. After rebuilding a few
HSTs, I am now of the opposite opinion and place a much lower value on gear-drive used
tractors.