PSU Upgrade Advice

[Spidernone]

That is my current build: https://pcpartpicker.com/list/3Pnn8Y
I am looking to upgrade the CPU to a 6600K to use the motherboard's potential. But I believe that I will need to change my current power supply which is Aerocool KCAS 500w. Those would be the power supplies I can get:
EVGA G2 - 550w $89.99 - 650w $85.68
EVGA G3 - 550w $59.99 - 650w $89.99
EVGA GQ - 650w $69.99
Corsair CX - 550w $44.99 - 650w $59.99
Corsair TXM - 650w $78.00
Seasonic FOCUS Plus - 550w $79.90 - 650w $89.90
Thermaltake Toughpower Grand RGB Gold - 650w $81.32

I read a lot about them but could not find which one would be the most appropriate.
Which one would be the best considering their prices? And how many wattages should be enough for overclocking CPU and GPU?

 

[jankerson]

Out of that list I would get:

EVGA G2 - 650w $85.68

Then the:

Seasonic FOCUS Plus - 550w $79.90

But then the EVGA G3 - 550w $59.99 is the best deal and a great unit.

 

[jawlesspython04]

I would just like to say that if you are worried about the noise of the PSU, Don't get the G3 as it has a loud fan. Seasonic Focus Plus is the quietest.