Side 100%. Can’t stand tall stuff!
I’m rebuying the battery grip for one of my S1Rii’s because it’s just a bit too unwieldy with the Sigma 28-105 f2.8, especially in portrait orientation where having that shutter trigger button is a boon.
That lens is only on the camera 20-25% of the time but it makes sense to just keep the battery grip on at all times for the constant familiarity in handling even with smaller & lighter primes plus it would be faff to keep switching.
On the other S1Rii, I have the Smallrig half cage which is basically just a base plate with a side rectangle that is supposed to protect any cables, but has 3 threaded holes.
Just a case of attaching the thingy that holds a P4 to that left side and then simply have it in the horizontal plane when I want to capture some gimbal video whilst shooting stills plus the ability to flip it to the portrait mode the rest of the time when I want to shoot social media BTS BS.
Also much easier workflow than shooting open gate and having to frame for both 16:9 and 9:16 in the same shot and sort through all that footage.
Less kit, less BS, better workflow.