I first saw a fellow member using a "Freecore" handle to replace his yonex racket. https://www.badmintoncentral.com/forums/index.php?threads/yonex-freecore.191028/#post-2871789 Based on what I have seen from victor's rackets, People have been saying it reduced vibration, increases repulsion, but loss of feel and takes a while to get used to. At times, I do have my tennis elbow flare up once in a while. I heard about reduced vibration, so I decided to swap out my handles on my Li Ning Aeronaut 9000C. AERONAUT 9000C by xZhongCheng posted Nov 13, 2023 at 11:01 PM I bought 3 of these handles for about $5 each from China. Upon first inspection, the handle seems to be decent quality. I stripped off the Original wood from my 9000C and sanded off the chunks off the graphite. Filled the entry for the shaft with gorilla super glue.I HIGHLY recommend another glue... one that holds very well but takes a long time to cure, maybe some kind of epoxy. The Gorilla Super glue seems to bond too fast so its hard to adjust the length and rotation of the racket head. I took the old screw and drilled a hole into the handle and shaft. Now onto the playability review: Vibration on hits was reduced as people have said, but i had much less feeling to my shots. Lifts and Clears - Felt effortless. I had trouble keeping my clears in. A lot had actually went out long. It will take time before I can control my lifts. Smashes - Will probably have to test this more. I tend to half smash more than full power smash. Accuracy and placement weren't an issue. I would maybe recommend stringing a pound lower. Felt like my racket actually became stiffer. Net play - Adjustment is much needed. Much of the net shots felt very off as threes little to no feedback. Shanks and Miss hits - I almost don't feel these at all. Even the very hard shots that end up hitting the frame.