I have a Kioti DK-40 shuttle shift and a Mahindra 2810HST in the yard. They are both great tractors and I use both a lot, but I prefer HST over the shuttle shift.
HST drives like no other transmission you have ever used.
It takes a little getting use to but you drive it like your riding the clutch you will get the hang of it right off, and your not hurting anything. It is the way your supposed to drive HST.
The other great thing about HST if your in low range and on a hill, when you take you foot off the pedal the tractor stops.
When your are in 4 wheel drive your front tires are braking also.
When you push the clutch in on the shuttle shift your are free wheeling and better have the other foot on the brake.
If your wife is going drive it she will like the HST better.
Good luck on what you get .
The truth is even though I like HST better, I just love driving tractors , what ever they are.
Dave in NH
Mahindra 2810HST , Kioti DK-40