All good.
I would add the
- Wharfedale Diamond 10.4 (£329/
pr)
- Acoustic Energy Neo 3 (£359/
pr)
if you want a real bargain -
- Tannoy Mercury V4 (£269/
pr)
I don't think you will have any problems with Yamaha amps, any of these speakers should work fine.
You need to evaluate the Bass Driver Size, though most will be 5". And you need to evaluate the low end response. The Tannoy above = 32hz. The Diamond 10.4 = 38hz. The Q Acoustic 2050i = 44hz. The Acoustic Energy Neo 3 = 43hz.
Keep in mind that numbers don't tell every thing. Those with the Acoustic Energy Neo 3 think the bass is pretty impressive.
Again, if at all possible, you need to listen and judge for yourself. I'm sure a great many people would find each of the speaker fantastic in their budget range.
I don't have the specs on the B&W 603, but they were probably more expensive than the other new speakers you are looking at when they were also new. The older B&W 603 still have many speakers in service, and the demand for those speakers is still reasonably high. It is a desirable speaker.
Mordaunt Short makes quality speakers, and the Aviano 6 originally sold for about £399/
pr. I can't find complete specs on them, so I don't know how large the drivers are or what the frequency response is, but I'm sure both are up to standards.
Curious, there doesn't seem to be a Yamaha CDS500, so I suspect you have either the CDS300 or the CDS700. The CDS300 is fine CD player in its price range. The CDS700 is in a MUCH higher price range and should perform accordingly.
That probably doesn't help, but in general, you have a nice selection of speakers. It is not a question of which is good, they are all good. The real question is, which do you like? Only you can determine that.
Steve/bluewizard