I really like the A49 amp...but you are matching it with 12,500 GBP speakers.
It should work, but you won't be getting the best from those speakers.
IMO. You should either get cheaper speakers, or a more expensive amplifier...like the Musical Fidelity Nu Vista 800.
I've heard the Kef Ref 3s with the A49, which sounded very well.
The Source will be crucial in that system......I would be using something like a Linn Akurate DS...or maybe a CDP from DCS or the Nu Vista CD Player.