It all comes down to what you are looking to spend. Of all of those the 290x 8GB edition is the best card, but is it $100 better, well that is up to you. For example for me 2x GTX 980 Asus Matrix graphics cards were worth the premium I paid for the look that matched my Motherboard and provided the overclocking headroom I desired. For many other people that would have been an enormous waste of money and they would have been better off buying a reference 980 that vented out the back. One other thing to note is what companies are these prices from, ex. are these all reference cards? Because that makes a big difference as well. While you pay a premium for non-reference cards, you also get increased cooling etc. So I am assuming that the 390 at $330 is a reference card while the 290x at $375 is not, which makes the 290x even better in my opinion.