Thanks for all the good info. I've found it extremely helpful, and I have to think other potential buyers will, too. Brochures and tire kicking and driving around a dealership only go so far.
I've been looking at a B2650, B2601, and L2501. I prefer to say under DPF/Regen HP, so these seem to be the best options to me. It's a horse farm, established pastures and fences, so mostly maintenance. Of course, once you have a tractor you end up finding uses for it that you never imagined when you started shopping.
The one thing about the L2501 that seems to give me heartburn is the fact that the split brakes are on the same side as the treadle pedal. So you have to be some sort of ballerina to use the brakes with your toes and hydro with your heel, or you have to have both feet on the right side of the hump or something. Maybe it's not that big of a deal nowadays, but I grew up on an 8N Ford and you steered with the brakes about as much as you did the steering wheel when doing any heavy work....