Soulgoober,
Ready for number and letter soup? I have the 640C v2 and really like it. I think the all-640 combination you suggest is over your $1000 budget new, yes? Unless you are looking to buy these used, which may be a good idea, you might consider getting the 540A v2 integrated amp and mating it with the 640C v2 CDP. The 540A has less juice than the 640A, but gets good reviews and just sounds really well balanced. The 640C v2 has the same dual DAC arrangement as the new 740C, and sounds noticeably better than the 540C, which actually sounds pretty good. If you are buying used, make sure both amp and CDP are version 2, since they are noticeably better than the original versions.
You might also take a look at Music Hall integrated amps and CDPs, as they sound great for that kind of money. My 2 cents.