Did you ever get a reply to your question with regards to the MSI GTX 560 ti & non ti? I tried looking for reviews on the non ti with no joy but loads of reviews on the ti version. I think better the devil you know. There has to be a valid reason why the non ti is cheaper & it's probably not a good reason.
actually i didn't get answer =(. However i went for a different brand; the GIGABYTE 560 Ti OC, this is because where i live the GIGABYTE 560 ti is actually cheaper than a regular EVGA or MSI 560 non ti (probably fees and shipping issues). Its a great card and runs very fast, not to mention it has two fans which cool it down.