Just thought I'd give my thoughts on these wheels as I've put about 3 hours of skating on them in the last few days. These are excellent downhill wheels and I think they're great for someone who's just getting into grippy squarelips and narrow setups like me. I've heard the urethane formula is similar to that of Venom Magnums, and the durometer of these is 75a which is right in between the available durometers of 74a and 76a that Magnums come in. These wheels definitely have a definitely edge grip and stopping power, especially when fresh with skin. Once they are broken in however, they become extremely easy to kick out at speeds, but while still retaining enough slowdown power to help you control your line while sliding. They seem decently durable, I've put the most skating on them at Blacks where I find that most soft wheels end up chunking. I think these wheels resist chunking fairly well due to the well supported lips. I find it hard to believe that it is the same urethane as Magnums as they feel a good bit slidier, but I could see it coming down to a difference in durometer and shape as well. Overall, at the price point, these are an extremely fair priced downhill wheel. The slide initiation feels safe and smooth. I have not had any highsides yet thought a few close calls that were issues with my weighting. I plan on picking up another set of these wheels once I am out of squarelips, and if you are planning on getting your first set of squarelips, these are a great and fun option. For reference, I have the white set, but the specs of the black set are the same, they may just feel slightly different in slide.