When I first started using my new Kubota more than 20 years ago I tried to figure out some convenient way to use the split brakes like we did on the old tractors. I remember moving a big round bale for a neighbor across the very muddy, slightly sloping cow lot next to his barn. The R4's weren't doing much good in all the mud and both the bale and the tractor were slowly working their way down the slope toward the fence instead of to the barn. Standing beside the fence, the old gent kept telling me to get on the brake, and I must have looked pretty funny doing some kind of dance on that tractor trying to find a way to do it.
The solution, when it came to me, wasn't some some really fancy footwork. In desperation I straightened the front wheels and punched the diff lock and the tractor began working its way through the mud toward the barn. Even with the slippy R4's , the "3 wheel drive" (1 locked rear axle + 1 open center front axle), gave more forward traction than I had ever been able to gain with the old rear drive + split brakes tractors long ago. We got the bale moved, but I don't think the old fellow ever figured out why I was doing that crazy dance up on the tractor.
I used the tractor for many more years doing many different chores, but the split brakes didn't factor in everyday use and weren't missed. For turning, if you have any kind of weight up front, such as the loader, with or without payload, the front wheels will pull you around a turn better than a brake turn in almost all conditions. And if it's a really sharp turn, the power steering + HST is so easy and quick to operate it makes sharp turns a piece of cake. I found adding a spinner to the steering wheel helps too.
Turning in slippery conditions is probably the one place where the split brakes probably give an advantage. If that's a big part of what you'll be dealing with, that odd Kubota pedal layout will be something to think about when you buy. For me, and I'd guess for most owners, it's mostly a non-issue.
