I don't know about bar lug tire comment...I was mowing on a damp roadside side slope last evening with my Ferris 2000z with their turf tires and was amazed at how that machine works in those conditions. The wide tire spread and very low center of gravity must be the reason. Ferris does say to always mow across slopes, not up and down. The tires that come with the machine almost never tear anything. Tire pressure is also key.

I can't imagine using bar type tires on a grass mower.