Yes Tom, I have used Marty several times in the past and I find it best to go and chat with him. That way you can discuss fabric, foam, gel needs etc. For me it's a 45 / 50 minute ride so it's not that bad for me. I think even if I lived further away I would make a trip of it.
Having said that he will willingly deal with it over the phone and by post. I sent him some picture of a seat that I saw in Alan Jeffries that was along the lines of what I wanted and we went from there.