no difference at all between tubular build vs clincher, in and of itself if all things equal. its all the same in reference to your weight, riding style, cadence--spinner vs gear masher, purpose of wheels--ie hill climbing vs all day touring, so generally especially with your choice, they are going to be overbuilt for 170lb'r, so go for longevity and do 3 cross, brass nipples and your going to probably never see the day you'll need to replace them