mark0680:up to £1500
I would suggest, Mark, you upgrade the CDP and amp. Probably the best place would be your local Sevenoaks or Audio-T. They usually have some very good ex-dem and s/hand stuff that will suit the RS8. Personally, I would audition Leema Pulse. Although it has a very agile delivery, match with a smooth CDP and the combo will sing! I heard the Leema/Arcam CD 192 and my RS6 - it made the hairs on the back of my neck stand up.
Sevenoaks Sound and Vision are currently selling the Pulse for £900 + £400 Arcam 192, that brings you £200 under your budget, and with that money you could upgrade your cables.
Good luck.
Edit - The quoted price for Arcam CD192 is on ebay.