First off, what is this build going to be for? Gaming?
Do you need the Extreme6 for a motherboard? You can get the Pro4, or Extreme4... Will save you money.
Why the i5-2500k, the i5-3570k is the same price and the 2500k and it current generation. If you plan on Overclocking you will need a better cooler for the 3570k though.
Personally I would go with Corsair (gold), or seasonic (gold) for the PSU, but I know nothing about the Rosewill one you selected.
Yeah mostly for gaming. All the parts came out to 479$,(wanted it under 500). I went with the extreme6 because the Ram came free with it. and Opps i meant to put Intel Core i5-3570K Ivy Bridge 3.4GHz (3.8GHz Turbo) LGA 1155 77W Quad-Core Desktop Processor Intel HD Graphics 4000 BX80637I53570K . Thanks