Moving SP2010 to a new SQL Server

I have a number of questions around moving from old SQL server to new one. 

Do the versions of the SQL instance have to be identical? I have been looking at this post http://www.toddklindt.com/blog/Lists/Posts/Post.aspx?ID=255 and it seems that the versions used here are very different but yet on other sites it says the versions have to be identical.

If I use aliases to point to the new instance will the ULS logs still report the original name or will it show the alias target?

Is there a best way to do this move operation? Should permissions automatically come across with a db attach?

Is backup and restore any better than detach/reattach?