There actually Pretty quiet, that center tread section is made just for highway driving.
I have these exact tire on my H3 going on 14 months. LOVE EM'! Here is my review:
Yes they are pretty quiet.....put after you put some miles on them and they are super loud, which i don't mind. Ride is smoother than my stock 31" tires. Tires are a little heavier than most 35" tires. Rotate often. Tread depth is holding up real nice after about 15,000 miles on them. About 85% tread left. Tires get mostly used for driving to and from work 5 days a week (total of 10 miles a day) and Muddin' on a weekends or more out the month.... Cane fields/cotton fields/ marsh type area. No 4x4 trails/rocks/ big logs/extreme angles in Louisiana. Final thought, these will be the only mud tires i buy for my H3 or any future 4x4 i own. They have saved my ass plenty of times in sticky mud.