Naim authorised service criteria.

I agree that some clarification would be useful. I did understand that other than Naim themselves, Class A in Sheffield are the only authorised service agent in the UK. Most of us probably know which service agents are definitely not authorised, and can’t be discussed here, but then there have been occasional references to other authorised dealers being able to offer some recap or other servicing. 

It mean't that the engineer had been to Naim and had some training on Naim kit and that their work was up to Naim standard, using Naim's preferred solder, and only ever using Naim parts, without applying any so-called "improvements", substitutions or short cuts of their own.

It's probably still that, but if you want to be sure, you can always ask them.

I do understand Naim trying to keep a grip on it by not allowing too many "rogue" ex employees trying  to explore and tarnish the company name by performing shoddy upgrades and below standard quality services but certainly there are a few good names out there who seem to offer extremely good service.