The advantages of the top mountmanifold versus the ram horn style is purely turbo position. The top mount allows for the use of a true 4" down pipe, makes servicing the turbo easier, and the height differential allows for a good turbo return line setup. The top mount also can accomodate large frame t4's like a GT42r where a ram horn, depending on maker might not fit that turbo. With that being said if you are not planning on running a turbo like a gt40 or bigger or a 4" DP then there is really no reason a top mount is going to be a better manifold than a ram horn. Hope this helps.