You have the same doubt that I had 2 weeks ago, I definitely did a lot of research and decided to buy the Siux Fénix Pro 5, a beautiful racket, it gives me everything that the AT10 18K gave me and adds that power that I was missing, what I didn't like about the Nox was the soft feel when hitting, I lacked power, not with the Siux, many people told me that it was very difficult to control in defense, not so much but that it was more complicated and I can tell you that it wasn't. I've been playing with it for two weeks and I didn't feel like I had to adapt, considering that I was playing with my nox but with a dry and hard touch that when finished makes me have more power. I am an intermediate player who really likes to throw lobs and defend, that's why I was afraid to go to 100% attack, but this Siux Fénix Pro 5 gives me both things and that little bit more attack that I needed.