Put it in this perspective, all 290/x are designed to work till 95 degC, be it any brand, model, ref/non-ref design. The only difference is in the cooling. AMD designed it such that as long as there is a fan to push all the heat out, it is okay liao. But, brands take a step further by designing their own heatsink and fan to further cool the card, thus allowing it to push further and gain more performance.
Do not think of that $100 difference as a loss for 1 day when you buy the card. Think of it being worth the 2-3 yrs you r gonna use the card. Is it worth it for you to face the heat output and noise level of a ref card or just pay extra $100 now and need not worry so much about noise n heat output.
Note that if u r gonna watercool (it does not mean slapping an asetek AIO cooler and G10 onto it), then my comment above do not apply. By all means get the ref card as custom heatsink does not matter.
My 2 cents.
