$750 or £500 Gaming Rig, Opinions please.

This is going to be my first Build from scratch so I just wanted some opinions on my current build plan.

I plan to use this PC for some pretty heavy gaming.

CPU: Intel i3-2100 3.1GHz 3mb Cache
http://www.ebuyer.com/254976-intel [...] 0623i32100

GPU: Gigabyte GTX 460 1GB DDR3 Overclocked Dual Fan Edition
http://www.ebuyer.com/232853-gigab [...] n460oc-1gi

MOBO: MSI P67A-GD53 (B3) P67 ATX Motherboard
http://www.ebuyer.com/261288-msi-p [...] a-gd53-b3-

Memory: 2x2GB G Skill 1600MHZ (9-9-9-24)
http://www.ebuyer.com/240501-g-ski [...] cl9d-4gbrl

Case and PSU: CoolerMaster Silencio 550 with CoolerMaster GX 550W PSU
http://www.ebuyer.com/267881-coole [...] 550-kka550

Extra Case Fan: CoolerMaster HAF 120mm
http://www.ebuyer.com/254078-coole [...] bb-08fk-r0

HDD: I am using my old HDD until prices start to fall
http://www.amazon.com/Seagate-ST31 [...] B000EA6WOO

What do you think of that build?

All opinions are greatly appreciated.

P.S: I would have liked to have got an i5-2500k, but due to my lack of funds I will wait until later to upgrade to an i5. In the futue I hope to add:

Another GTX 460 in crossfire
A 1000W PSU
i5-2500k
An SSD boot-up drive

Then overclock the S**t out of it! Good Plan?

Go with the i5 2500k straight up, you're using $750 for this comp, anything over $700 and I'll put a i5 in.

Oh yeah, it's worth it. I have the i5 2500k and I have boot times of like 10 seconds (and I don't even have a SSD). If you can, definitely get the i5 2500k.

Nope! The i5 is the same as the i3, a 95W CPU, although you might want a higher Wattage PSU if you plan to SLI.

Your build looks decent. However if you magically have a $70 lying around, you can get the Asus Maximus Gene Z if you are into overclocking. Although it's m-ATX...