I have tried most all and also choose the Marsupial. A lid that opens up is a deal breaker. In good weather I want the bucket open so I can pull out the binos frequently and drop back in one handed. I think a medium would be what you need. I run a small with 8X32 EL's.I've tried AGC, FHF - I decided on the Marsupial - I like the way the top lid opens away from your body and the ability to keep the lid in the open position without interfering with the removal or storing of the binos.
I think a Marsupial size large would fit both binos you have - the only difference in the size on the Marsupial is the length of the lid - the bottom portion that the optic sits in is the same on all sizes.