Yes and yes!
I'm running the 8's and the run time is pretty decent. From memory I think I roughly get about 90 mins continuous cutting before they hit the 1/3rd level.
Just checked my batteries and I thought one set was 5.0ah but it's 5.2ah, don't know if the dimensions vary from the 5.0ah, but the 8ah's are the exact same height as the 5.2's, and fit just fine packed inside the case and don't protrude, although they are longer, which Festool have catered for as there's still more room at the end.
[attachimg=1]
[attachimg=2]