I had a Jan 04 Dark Silver/White S until the start of this month, and I changed it to a June 06 Checkmate S. The changes, aside from the cosmetic - different rear lights/different xenons - are noticable. The gearbox feels freer, and the clutch isn't as stiff. Acceleration seems a little quicker too, and it possibly pulls away a little more cleanly too.
As mentioned above, best thing for you to do is to try the two out. I don't think you'd be disappointed with either, should you find a pre-facelift model that's the right spec and price for you
Good luck!