It matters depending on your 360, your burner and the brand of blanks you use.
I have verbatims, and one 360 will happily read them burned at 8x, but the other won't reliably read them unless they are burned at 2.4x.
Just because something works for one person, doesn't mean it is the same for everyone.
I know tend to burn at 2.4x, you only ever do it once when you first open up yr minty new game, so the wait to burn doesn't really matter in the scheme of things, unless yr running some pirate duplication operation or something.