I am going to be replacing old copper lines in a home. I currently have a 1" line entering the home and within a few feet, it gets reduced to 1/2. I will be installing PEX manifolds and am wondering if there is an advantage to maintain the 1" line to the input to the manifold. All of the manifolds I can find, are 1" copper with 3/4 pex inputs. If you have a 3/4 " pex fitting on a manifod, is there an advantage to use 1" Pex to that fitting, or did any "volume" advantage disappear with the reduction to the 3/4" input. Thanks for your help