corsiar no question. They seem to have the best compatibility from past experience.
Edit: Now that i have time to write a full post, i'd like to ask you what board you'll be using. I know the gigabyte ones (ds3, s3, dq6) support the OCZ so getting corsiar for them won't be necessary. Never worked with Geil so i reserve my judgement.
Asus P5W 64 WS Pro
DFI 975 Infinity
Intel Bad Axe2
my original choice was the asus but it's £30 more than the intel, £60 more than the MSI and £80 more than the DFI.
thing is MSI and DFI were rubbish 5 years ago when I was a network admin if you wanted to do overclocking etc. they were just a good cheap board to stick in a standard system. Of course things have changed now but the likes of ASus and Intel still (rightly in my opinion) command a premium.
however, past experience with Intel has shown their BIOS is never a Over clockable as competitors.
I'm just reading about the bad axe2 now because I previously didn't give intel a second glance and it seems they aren't too shabby at this point.
I did consider the Abit AW9D for about two seconds but it hasn't got a parallel port.
All of the above have at least 2 PCI-E x16, 2 PCI, ata, sata, and external firewire and parallel ports.
oh... those boards i've never worked with, All 3 different models of ram you picked "should" work but i haven't had any experience with neither those boards or the chipset. Corsiar is the safest as that seems to have universal compatibility. Perhaps some one else can give better advice.
wasn't there some discussion recently about D9 chips and corsair? something about them switching to a cheaper manufacturer but not dropping their prices?
in fact, found that article on the xtreme systems forum.
someone on that site forum did say that crucial were owned by micron so that I should consider crucial ballistix 2x1gb kit at 6400 80 which is priced the same as the corsair memory, also from overclockers.
someone else said ballitix was very unstable and you have to play with it in the bios.