I've two Nolan helmets with Nolan intercom installed.
They are both size L. One is the flip-face N104 with the B4 set and the other is the new N44 with the B5 set.

They both fit in the middle of either bag. The sweet spot is to tilt the upright helmet sideways such that it's lower side lip is above the ridge that runs obliquely along the back of the bag, (as you look into it). Neither helmet will comfortably fit sitting flat on the floor of the bags.

FYI, The Nolan intercom sets don't stick out very much from the helmet, compared with some others I've seen.