The EOS-M. It allows you to take all your existing EF lens with an adapter. It’s quite a joy to be using light(er) equipment compared to the usual 5DMK3 coupled with the EF 8-15mm
4 Shots around pano are totally possible. Shown below, the EF 8-15mm with the adapter.
Removable tripod mount.
and who can resists trying out the 580EX flash + the 70-200 II f2.8 on this!
The setup with the nodal ninja R series tripod head. No changes to the adjustment needed.