<font color="blue"> So how do you find the difference in tires as far as leaving marks in turf? </font>
Big difference, the R4s have no "give" to them (thats what makes them great for loader use). The turfs are much more compliant. If you slip with the turfs, you can mark up the grass, but at least you don't dig a hole like the R4s.
My yard is full of obstacles, trees fence etc. I have to turn alot while mowing, thats when the R4 front tires would leave a mark, especially on a hill.
My soil is pretty soft, if you have hard clay, your milage may vary.