This cube was the worst decision I have made about rubiks cubes. I'm a beginner on the 4x4 and I was getting the cube that looked the coolest. This cube broke within minutes of first use. Not completely, but a piece popped off. Pieces pop very easily on this cube and it is not pleasing. It's easy to put back but it's annoying. after a week of use the cube broke down to the center. DON'T BUY THIS CUBE.

I actually ordered this cube on accident (I meant to order the 5x5 from Qiyi). Thankfully, I've ordered a Cyclone Boys 4x4. I only hope that the Cyclone Boys cube holds up to it's reviews.
I won't be ordered the Qiyi 5x5 now. I'll most likely just spend the money for the Moyu AoChuang. I'm only a casual cuber, and I'm particular to the stickerless variety.
This was the first 4x4 I purchased. When it popped yesterday (really... It exploded) I had no idea what to do. It's not a very popular cube, so there were no resources on how to put it back together. Fortunately, this seems to be a cheap knock off of a Moyu Weisu, which there are videos of.
The internal parts do not fit together very tightly. After finally managing to reassemble the cube I began a solve. It had two minor pops then exploded again. I've done what I can to adjust the tensions. But now, since the explosions it seems more prone to catch on the outer layers.
I didn't expect a speed cube when I bought this. Really, I didn't want one. Just something affordable so I could learn a 4x4. What I ended up with is a cube that I have to worry now whether it will even stay together. I've had it a week? Awful.
I'll post some thoughts on the Cyclone Boys cube one if arrives and I've had a chance to break it in. But, I can say with confidence not to trust the Qiyi 4x4. For somebody who's best 3x3 solve is 50 seconds I find it hard to believe I could be trying to turn this cube to fast to the point now it seems completely unstable. I think the problem is this is just poorly designed and/or defective cube.

Cube is not very good at all it pops all the time and even internal pieces fly out very dry and the inner layers are stiff and the pieces all scrape to make the cube very slow I don't solve it at all I put it back in the box and dont use it anymore

Awesome colors, cam in and worked perfect! Loved it!

When I bought this cube, I loved the colors. However, it was somewhat stiff to move. A couple days later, it popped on the inside and then all of the pieces fell out. I could not figure out how to put it back together, and I put all the pieces in a bad because I was too frustrated to put it back together. I would not recommend this cube to someone without extreme slight of hand.