I have found that the quietest soles are air bob soles and they also give the best grip on the most different type of surfaces. They are softer than most types of soles and tend to flex and absorb inconsistencies. Vibram type soles just dig in and won't flex unless really well worn/broken in. Step on a stick with airbob soles and it may not break but with a vibram type sole it will. Also if your on alot of rock the air bob soles wear very rapidly and can get expensive. Hope it helps.