Simon
I'm pretty sure mine is this one :-
https://www.wexphotovideo.com/lowepro-nova-sh-180-aw-ii-black-1636062/
But I don't think I paid that much for it, so maybe slightly wrong model, will check when I get home.
If it's the one it carries my Olly EM1.2, the 12-40 and 40-150 f/2.8 PRO lenses + grip, and would if needed fit another 2 (small) lenses (of similar size to the 12-40, but not another 40-150). It could probably hold the camera with grip fitted but I don't generally use the grip. If grip was fitted it'd probably require moving a velcro divider side-ways and maybe not having room for a 3rd lens, or at least it'd be squished underneath the camera / grip.
For me it's perfect as it's exactly the right depth for the Olly 40-150 f/2.8, even with the MC14 fitted. I have batteries and cards in a pocket on the lid, lens caps and some other bits in an inside pocket, and filters and some other bits in front pocket, so it currently takes ALL my gear. It doesn't have a strap for a monopod however, which I miss from my back-pack, although my m4/3 gear is so light I don't need the monopod anymore to be fair. It also has a permanently attached pull-out rain cover inside the front pocket.
Shoulder strap is big and comfy, and it's a doddle to swing round / open up etc. without putting it down, the thing I hated about my old back-pack.
My only issue is it takes the camera with 12-40 f/2.8 fitted, but not with 40-150 f/2.8 fitted, so if I'm using the 40-150 and want to put my gear away to move on, I need to swap lenses then stow everything away.
edit: just checked my Wex order history, my bag is the Lowepro Nova 180, but it doesn't have "SH" in the model no. and was £20 less than the one linked above, still looks the same though.