Greg,
I can assure you that the B7610 DOES have cruise control. It is one of the two orange levers on the vertical dash panel. It is not as sophisticated as some of the other models. Nonetheless, you can use the lever to set a particular speed and take your foot off the pedal. Tapping the pedal disengages it.
As far as usefulness goes, I have never found a use for it, other than playing with it to see if it works. I use my tractor for finish mowing, brush hogging, tilling, snow blowing and more.
You can use the link below to see photos of my Killer B7610. Good luck, and enjoy the hunt!