Sport razor works great. This is my 3rd one over somewhere around 10 years. Unfortunately, the finger ring breaks after years of use (reason for 4 stars, even though it has not had the problem). That is part of the reason I am now on number 3.
I also recently purchased an ATX razor. I have only used it about 10 times, but I think I like it better. The finger ring is split into two and both are shorter. I hope this means it will not break. Also, there is a finger rest right behind the ring to help stabilize the razor. It is a pull blade rather than the push blade on the Sport. Might mean less cuts. I have not cut my heat with the ATX as yet. They are both great razors!