Accuphase Class A or A/B speaker match Dynaudio C1

I am driving the C1's with a Jeff Rowland Concentra II, 150w into 8 ohms 250w into 4 ohms. This works fine but is probably the minimum I would find acceptable. I have also heard the C1's driven by Simaudio W7, this was not lacking for power either.
I have found the sound balance to be excellent at low levels with my set up, none of the hissy/tinkly sound you get with metal tweeters

Roy, you should not think at future changes before actually having bought the whole system, viz. "the E-550 may? Limit the range/scope of future speakers". Since you plan to buy top of the line integrated and speakers (it is not clear to me whether you already have the C1s) make sure you are happy with both units as a whole but also separately. The E-550 is very powerful (much more than its 30 watts would suggest) and should have no problem to drive almost all monitors. I have seen this amp driving speakers like Wilson Sophia 2 and B&W 802D without a sweet. Though, if you listen to music that has large dynamic variation, e.g. big bands, than probably E-450 is a better choice whatever the speaker.

If you have already listen and liked the Dynaudio & Accuphase combination then choosing between the E-550 and E-450 integrated should not be difficult. The power meters should give you the answer. If you can not audition both amps in your room (for a few days) take your speakers to the dealer. Get the E-550 if it is not clipping when driving the C1s at levels you consider as being loud, otherwise buy the E-450. Sound-wise the two amps are very similar. Although, the E-550 is more musical and fluid than E-450, you can't possibly be happy with it if it can not deliver the SPL you want.

Forget Accuphase integrateds and try the german amplifier ASR Emitter II (it's also an integrated amplifier with separate supply units).

Okocza, price-wise the ASR Emitter II integrated is in the same class with the Accuphase separates, e.g. P7100 power amp & C-2410 pre amp. That is 3-4 times more expensive that the Accuphase integrated considered by Royearnest.

It seems I was mistaken in my previous post. Here in Europe the Emitter 2 retails at around 13 thousands euros. That is a bit less than the retail price of the entry level Accuphase separates, i.e. P-4100 and C-2110, which retail at 13900 euros. When new, the E-550 was 8500 euro. Thus, it may be possible that the 2nd hand prices for the two units (E-550 and Emitter 2) are not that different. Sorry Okocza.