I have a stickerless dayan zhanchi I got from cube depot, but it doesn't have that speed that I've seen in reviews, and where is a good place to learn advanced intuitive f2l? I know beginners, but not advanced. I also have the finger speed to be getting sub 20 solves off of a beginners not f2l method, but my cube is slowing me own, it's never been lubed and I'm not sure if it's tensioned right.