Bz,
I have a Case 450C dozer which is perfect for ranch work, land/brush clearing, pond maintenance/renovation, and fence row clean-out...but not enough dozer to build a 5 acre pond from scratch in any reasonable amount of time. I'll rent the large dozer and track-hoe for larger pond building hopefully starting again this fall and continue to keep the 450 for general purpose use. They are really useful machines where property maintenance is involved.