There would be some speed loss and possible noise but nothing that would keep me from using a tube if that's what I wanted. I have a good, quality string and don't have an issue with the peep twisting. The main reason is I was shooting with a friend who had a tube and it broke and he had a hard time getting it back on and working. He eventually got it to work to shoot some more but it was enough to tell me that was something I'd rather not have to depend on to shoot. I had trouble seeing thru the regular peeps at low light till I went to the fiber optic and then the NightHawk, which was actually better. I shot for a while w/o a peep and shot fairly well, I just like using a peep and for me, it seems to help with accuracy.