My system is comprised of products from may different vendors (Vandersteen, Atma-Sphere, Modwright, Logitech, Plinius, Running Springs Audio, Sistrum, Furman, Kaplan Cable, Reality Cables, and a few others).
Personally, I am vendor agnostic and simply go with what sounds best and fits within my budget. Even if I have a very positive experience with a particular vendor and currently own their products, I am not afraid to replace their product if I can improve things.
George