You realize the 5850 you linked isn't in stock right? So... not exactly a comparison with an instock card.
My point was that you should wait for the best card you can purchase.
Not to mention you're linking ONE card that is labelled "5800". The usual run of the mill 5850 gets nowhere near 400MHash/sec, even on water that's hard. To say you can consistently get 380 out of 5850s would be a stretch.
If this is true then it changes things. I was going with hard facts I found on the web. I also get top megahash per sec out of my 5830's (320) without watercooling and it runs around 68c so I assumed it would be fairly easy to reach this mark.
The 5830s are available, and they're close to the top in terms of $/MHash, so if you're going to get a card, this would probably be it (though the power consumption is an issue of course). If you argue against getting a 5830 then you argue against getting any other card basically.
I'm not saying the 5830's aren't the top in terms of megahash per dollar but you should still pay for only the most efficient cards you can get. Why pay 130 for the same card that comes in stock at 110 every couple of days?
I don't need to do some research because I have 3x6970s, 4x5850s and 4x5830s all currently mining for me. I just "don't" read research, I based it from my experience.
Next time buy the product and post the facts based on your experience.
My question to you is why do you have 3 servers with 3 different cards? If you knew you were going invest heavily into bitcoins I would think you would pick the best card you could so you saved yourself the most money possible.
Also basing it off experience is like saying I know this works trust me. Basing it off research is like saying here are some articles that list bench marks you can figure out for yourself what the best card is.
Uhm, every couple of days? Not sure where you are getting that from, search the forums for the last time that the $110 sapphires went in stock. Was weeks ago. And I'd be willing to bet you will basically never see them in stock again. The $130s are here, they will be in stock for a while, when they are gone they will likely be near to the end of the 58xx retail batches. That's why I don't care about the 5850s you linked, because they're not ever coming back. Same with the sapphire 5850 extremes, they were good buys, but they're gone, so they're irrelevant.
I'm not actually advocating buying these, because with the increase in difficulty, the decrease in price per bitcoin, and the lack of resalability once the bitcoin craze dies down, these cards will likely be big losers, BUT if you are looking to buy a card, they are near to the top of the heap for mining, so there's really no reason not to grab them.