Which GTX 970 Version is the best?

I'm looking to upgrade my graphics card from a Radeon 7850 to a GTX 970. I'm not sure which 970 model to get but I'm looking at the Asus Strix GTX 970 and the MSI GTX 970. I have a 500w psu and would like to keep the psu and gpu compatible. I'm leaning towards the MSI GTX 970 because it has good performance and works with my psu. 

Thanks

SPECS:
CPU: AMD FX 6300 3.5ghz
COOLER: Cooler Master Hyper 212 Evo
MOBO: MSI 970A-G43
RAM: G.Skill Ripjaws 8gb
STORAGE: WD 1tb
GPU: MSI Radeon HD 7850 2gb
PSU: Corsair CX500M
CASE: CM HAF 912

Arguably the GIGABYTE G1 Gaming version of the GTX 970. It's one of the few GTX 970's that for some reason is pulling the highest overclocks. but these cards are binned so it's expected. but remember the "Silicon Lottery" is still something to keep in mind, a lot of people are pulling massive overclocks but that doesn't always mean you will as well.

G1 and MSI both get about the same clocks and preferred IMO. Silicon lottery dictates it more than anything. You could get a Strix if you want "gamer bling" but I don't really like it. I feel restricted by the single 8 pin. Although if you are going to out of box performance or only OC it on air then the Strix can do you fine. Its very specific to your situation which card is best.

G1 gaming because of binning, or the 4G MSI gaming editions orange/black, but good luck finding those. I think i bought the last 3 in the world it seems lol :(

A few hundred mhz makes little difference whereas a few $'s saved will buy a couple of strawberry malts so you can treat yourself and your favourite gal ;)

Get the cheapest one with a dual fan cooler imo.  If it was me I would get this one.

http://www.amazon.com/EVGA-GeForce-Superclocked-Graphics-04G-P4-2974-KR/dp/B00NVODXR4/ref=sr_1_1?s=pc&ie=UTF8&qid=1421437998&sr=1-1&keywords=gtx+970