Hi, I own a CS600 as well and use it to drive pair of Merlin TSMs. they are a fantastic match and have the combination for more than 18 months now.
I would guess that the Proac D2s would do very well as would Devore (I have heard them with Devore entry level floorstander)
another speaker in the same range could be Green mountain Audio Eos
I would guess that the Proac D2s would do very well as would Devore (I have heard them with Devore entry level floorstander)
another speaker in the same range could be Green mountain Audio Eos