I agree with Ian, if the 6000s are already 96/24 I think you'll get a more significant impact by going for a 7200 as a centre, with a much much better bang for buck ratio.

If the 6000s are old it might be worth checking the tweeters - these do seem to get old and start rolling off the frequency response rather than fail totally.

But, of course if you lust after some new speakers the 7200s are very nice.

I can't comment on the US market for 6000s but I suspect it is driven by a view that they are great value speaker (great speaker - available at low cost) so the price will tend to be pushed down. Will also depend to some extent on exactly which model it is.

Chris

Lounge/Cinema, Trinnov, DSP8000XE, 4x 320.2 in-ceiling, M6 rear, 2x DSW.2
Roon Nucleus+ and 320.2 in-ceiling in many rooms (KEF in-ceiling in bathrooms)
Spare: DSP5000, 598, 562v2, 500Mk2, 518, 519, 504, 101B, M3, 861v4, 800 DVD, MS600, MC200