well my thoughts are that it is just too expencive. I would go with a nice water cooling unit. It would be BA to have your opty running at -5c at full load oced like mad but you might have an opty with a cold bug, that is the chip doesn't work when running at below freezing temps.
you can save a good chunk of change by just going with water and you should still be able to oc a lot too.
i dont see how you say that the vapochill is too expensive, you must not have looked at the link, its not talking about a phase-changer, it is talking about a Vapochill Micro that will cost $49-$59 thats not bad for a cpu cooler. you couldnt get any quality watercooling setup for that money
So anyway back to the topic i'm not sure how the Vapochill Micro will perform but have read a few reviews on some of their other products that have gotten good reviews. it should do you well , read these reviews to get a better idea for which particular one you want
reviews for the
vapochill micro and
one here too
US prices for the Vapochill Micro....
HERE
Another cooler to check out
Zalman CNPS9500 for $62.99 its good cooler too