Best Memory For New Sandy Bridge Based PC Build

Guys Please help! - this is my first new system build in 9 years and I want to get the perfect match of components.

My new PC is based around the new Intel i7 2600k CPU and an ASUS P8P67 Motherboard. I've also decided on the ATI Radeon HD6950 Video Card.

I've asked elsewhere on the forums for advice on what factors help in deciding between a 32bit or 64bit Windows OS so just want help on deciding on brand and model of memory at this moment in time.

I'm struggling on what memory to go for and have no idea how you decide on these things (besides budget)

I've narrowed my memory shortlist down to:

Corsair 4GB XMS3 DDR3 1600MHz
Geil 4GB DDR3 1600MHz Value Plus Dual Channel Kit
Corsair Dominator DDR3 4GB 1600MHz Dual Channel Kit

Can anyone please tell me which memory would be the best match for my new system even if it hasn't made my shortlist?

Big thanks in advance.

would like to know this too, also whats the deal with 1.5v v1.65.

any thoughts on this - anyone - please?

waiting to order some memory and no idea what to go with :(