I forget actual weight, but those are smaller, lighter and sometimes thats just the right size for a lot of types of work. I have ran 450 Case, but a long time ago, never spent a lot of time on it, but one outfit I worked for had several brands in their fleet, and it was interesting to me as an operator, to try each one out when it was on the job I was assigned, a couple of us operators would volunteer to switch from machines we were assigned, so we were good on anything they owned. I do recall the 850 case much better, say late 80s vintage, aside from the small steering levers on a pedestal, just something to get used to, from pushing off fill, grading and or cutting, I liked the 850 Case. This outfit had 2 identical 850's easy haul on a tandem tag trailer,(8 wheel)with air brakes, I would assume, but have never hauled the 450, even lighter, would seem a one ton properly equipped with appropriate trailer, should be ok to move one, don't quote me, numbers don't lie, but my long winded talk may LOL !!! (not intentional - stand to be corrected)
I would agree with JD Maris on the 350's and 450's, I've run those and a 1010, condition is important, Case seems to be the better bet, parts availability and operation costs associated, seems their older crawlers have decent parts support, or it appeared that way.