Benefits of brand synergy

There is benefit in synergy.

Buying all within a brand does not necessarily guarantee synergy, so careful there. Some gear in some brand lines together might provide it, some not.

Don't forget also that whatever gear you buy has to synergize with the room and your listening position as well. That is equally important, perhaps even more so. You might also have to buy trusted consulting services to get that part right if not comfortable doing it yourself.

(1). Using the same brand can offer freedom from technical incompatibility, take full advantage of "brand features", and possibly eliminate a better performing specific component(s), double up on brand coloration's, and possibly provide symmetry in shape, size and appearance which may or may not help with placement, is a safer route for novices and potentially compromising for experienced users.
(2).Using different brands can increase the chances of technical incompatibility, reduce the advantages of "brand features", maximize the possibility of using better performing specific component(s), counter brand coloration's, possible asymmetry in shape, size and apperance which may or may not make for more challenging placement, may be a riskier route for novices and possibly offer ultimate performance for experienced users.

Don't know too much about Naim, but is it possible to use Naim with non-Naim?

Many good answers above. On the basis of sound quality alone it depends on if you like the sound. Of all the one brand systems I have heard there were not many that were outstanding. It is very difficult for any one manufacturer to design one very good component let alone several. I prefer to mix and match. It is more difficult and time consuming but can yeild superior results. It can also be frustrating some times.

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I bought two pairs of Pass Labs X-600 monoblocs and a Pass Labs X-02 preamp. The sound was very good. I inserted an Audio Research Ref2 MkII instead of the Pass preamp and got immediate improvement. I again inserted an Audio Research Reference 3 preamp into the system, it was head and shoulders above the Pass Labs preamp. Both preamps were $10k at the time and both were flagship preamps of their company at the time. For me, this blew a huge hole in the brand symmetry theory. Brand symmetry sounds like a good idea, but I still believe that you have to listen and audition multiple components to see what works for you.
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