I'm working on upgrading Sitecore 7.0 to 7.5
According to Compatibility Table, I have to use MVC5 from 7.2. I already have MVC3 layout for 7.0 and created new MVC5 layouts for 7.5.
I placed both versions of related files (dll, cshtml and cs) in each 7.0 and 7.5 version to see differences and what error shows me. But, two versions are working well in both versions.
Could I know some more detail about these differences in different Sitecore version?
That is true, they both will work. The difference comes into a play when you'd like to use MVC 5.1 specific features. Also, if you reference asssemblies for 5.1 in web.config for your views folder - you get extended intellisense and VS will not highlight errors for new api from 5.1