The PC 10 arrived yesterday and it is exactly as advertised.
It is bigger than the TT 10 in real terms, being squarer and deeper overall. My 40-150 f2.8 with a screw on metal hood (much less fragile than the Olympus one), sits in it nose down as does another zoom (8-18) and EM1x body or G9 and third lens. This is ideal as my sports companion.
They look similar here.
My F2 will remain my day bag though, because I have found it very useful for taking notes on with a A5 note pad. The pad sits on top, which allows me to shoot and take names as I go.
Full, this bag feels heavy, so I guess the bigger 13 would be quite uncomfortable full.