I have recently received my Dayan 5 ZhanChi cube that I bought on eBay for 17 bucks. It came from Hong Kong from a trusted seller, and I have to say that I am disappointed. The puzzle was protected, undamaged and looks perfectly fine, but it does not turn smoothly and it takes quite a bit of effort to turn with single fingers. As for corner cutting, it can cut no more than 30 degree angles. (with adjusted tensions) I also tried taking the torpedoes out and that didn't help. I don't know what lubricant I should be using, if any, and I'm very confused because reviews on youtube show the cube being incredible straight out of the box. And advice would be greatly appreciated!