The Terrapin X delta cut (centering) keeps the string dead center all the time. It is coated in dryplay which means that you don’t have to lube the bearing, although this makes it quite noisy out of box. Mine did not take long to break in and become quieter though. The sleep time is pretty good. I was replacing my ten ball with the Terrapin, and it did increase the sleep time. It also made my yoyo more stable on the string. This or a Crucial groove would be my best advice for you. ( I don’t know much about the Crucial, but I have heard great things about them, and I just ordered two of them yesterday).