Well, there are good reasons why Naim use (and have used) DINs. You can read a bit about why, here;
As for XLRs, Naim’s view was that “The XLR connector, at its best is only as good as an average DIN plug; the best DIN plug has absolutely no peer”. Naim supposedly only used XLRs on the NAP250 because of the expectation in some quarters at the time that a “professional” amp had to use them. They continued with them as they were useful to differentiate between the regulated power amps with no in-built pre-amp supply to those unregulated with an in-built pre-amp supply. It helped that Naim had designed a special low mass XLR plug to optimise performance.
Of course, move to a balanced system and the use of XLRs is pretty much obligatory…