PSA: You will (most likely) not lose relative GVR FOV with the S7 Edge

Among other reasons, people generally preferred the Note 5 and S6 Edge+ for their increased FOV over the regular S6 and S6 Edge. That was because the regular S6 and S6 Edge had smaller display sizes than what the optical system of the Gear VR could maximally see, horizontally. And actually, if you measure the shape and size of the encasing (the "hollowed" out compartments between the display and the lenses seen here), it's smaller in both horizontal and vertical size than the 5.7" displays of the Note 5 and Edge+. You can also see in the rendered screen that the full horizontal and vertical space is not reached - those dark areas of the display aren't being used, and mostly can't be seen through the encasing anyway. The 5.5" display on the S7 Edge should actually fit very well the horizontal size (the vertical is already being limited so much anyway, so no point in comparing that, I guess).

So essentially you'll get the maximum FOV out of the Gear VR with the S7 Edge. At this point, it's not the display limiting the FOV, it's the Gear VR itself, unlike with the regular S7, S6, and S6 Edge, where the display is the limiting factor. Hope this clears things up for anyone who was wondering. There are still many other factors to consider if we're talking about buying decisions. This is only one thing.