You might want to clarify what kind of cruise control. All the x55 tractors starting with the first models in 1986 had cruise. However it is a totally mechanical system and rather sloppy to use. I never use mine. Why do you want to know?
I can't afford a new tractor and am starting to look at used. Would like a hydro tractor with cruise. I've used a 4600 with the push button cruise for tilling - mowing etc. I don't think for slow steady projects that I would want a tractor without it.