I think this would really come down to brand preferrence...though I think you were probably expecting that kind of answer.
Leadtek, generally speaking, have a far greater track record for videocards than MSI, being some of the most popular cards back when the Ti series came out (for their nifty cooling setups, if anything else
).
I've used both cards, Leadtek for a Ti4600 and 7800GTX, and MSI for a pair of 6600gt's. I can't really fault either in a comparative sense, they both performed amicably, with the only real difference being in the software package. With Leadtek you generally get 1 or two high quality games, and depending on where you shop, with MSI you may get a heap of older games, or no games at all...
All I can say really is, look at the software packages provided by either brand for the particular card you want..and if that doesn't tide you over, go for the card that looks better!
*EDIT* - I should probably mention, in terms of noise, both cards should be using pretty much identical coolers, which, by the way, are near-silent anyway. Memory should also be pretty much identical on both cards....though if I had to guess what brand would be more likely to include superior memory, i'd be aiming at Leadtek. As for 2d image quality, since both brands' cards are identical bar their supplied software and/or stickers, there should be no difference. Hope that helps
