Won't matter a heck of a lot, however, OC edition should have voltage control, so if you aspire to overclock your cards that's very important. Not sure if the MSI one has that, although since MSI makes Afterburner I would have to think it would work with it as well.
So basically, if OCing is imporant to you pick the one with unlocked voltage control. If it's not imporant or if they both have it, just go with the cheaper one.
If noise is a huge issue to you then I don't know, you'll have to read some reviews that compare noise lol. But IMO it won't matter, they're almost guaranteed to be quieter than the reference fan and it cools my OCed 5850s fine.