I took the same size in the 341 as I did in the 348. Although I must admit the 341 was so snug at first that I didn't think it was going to work out. The issue being the width at the toes. So I would say the 341 is just a smidge narrower than the 348 at the toes.
Does anyone here own the Mertons and wear them with shorts? I am looking for a new pair of casual loafer (looking at the Mertons in Mink Suede) and wondering if the 348 last is too long / looks awkward in shorts and if I should choose a more rounded last.
I have black suede Mertons but would not wear them with shorts. My brown suede Cavendish are fine though.