I took the plunge and put hard earned money down for the OCZ 2GB Kit (1GBx2) PC2-6400 Dual Channel Platinum Revision 2 XTC Series DDR2 (model OCZ2P800R22GK) over at Overclockers UK who have it at a special price of £117.49 (inc VAT).
I also plumped for Corsair HX 520W ATX2.2 Modular PSU priced at £70.49 at Overclockers UK as well.
I did fit the memory and not the PSU (will wait to get a new motherboard before I gut my system again) and all worked OK out the box. I noticed on their support site that the specified timings of 4-4-4-15 at 800MHz are not in the memory's SPD timing table and need to be entered manually into the BIOS (so much for not going Corsair).
I have been running them for 3 days and have stress tested them and they see OK, not really a speed boost I had hoped for with 2GB but suppose I wont know till they are really running at 800MHz (currently at 677MHz due to motherboard limitations).