I have own the McCormack DNA 225 amp, it is an excellent ss design from a well established company(currently owned by Conrad and Johnson). Build quality is excellent with quality parts. I haven't heard the Marsh amps but they have received excellent reviews in The Absolute Sound. If you have the chance listen to both in your system. I don't think you could go wrong with either one but I bought the McCormack based on sound, company reputation, dealer network and support. Good luck.
