Well you've made the right choice so far by looking at a Kubota. I couldn't tell you about the updated cooling system or water pump. But I can tell you rest assured you'll be pleased with the B7100. I myself have a B6100 and have been blown away with the kind of things I can do with such a small tractor. So far I've had no major issues with my B6100 which is a smilier model to the B7100, mine is a 14hp and I believe the B7100 is 16hp. Really all depends on how the previous owner treated the tractor, weather they took good care of it or used and abused the tractor. They really need to have a Sherman Tank emblem on these things because a Kubota is tough as nails.