For all these reasons, I voted Sig. I especially like how the hammer gently rides the decocker as it moves back upward under the thumb. The only downside is, as someone else mentioned, the slide stop is not in the "universal" position. To me, if one is going to carry a classic Sig, it's worth considering committing to them 100 percent so muscle memory can be counted on.
I've never heard of that criticism, either. I'll point out that it doesn't appear in the video that Ernest is in any danger of actually experiencing that with his grip. Far more common to have a failure to lock back due to thumbing the slide stop while firing. For a righty, getting your strong hand thumb outside the support hand thumb, or just flagged up/outward, will solve that.
I kinda feel like Ernest's criticisms fail to contemplate the totality of the Sig design. The not-quite-down position the hammer decocks to is its actual rest position. There is a little return spring that holds it back in that position, so it's away from the firing pin. It won't go forward of that position without the inertia of a mainspring-driven drop. Further, there's a block that prevents it moving forward past that position unless the trigger is pressed. Since this is simply the rest position, it's always going to be the starting point of a DA press. I don't understand what it has to do with the SA notch.
I'd also be curious to hear whether anyone has an anecdote of something actually getting into the gap between the slide/firing pin and hammer and preventing a Sig from going bang. It's certainly massively less likely to happen than with an SA carried in Condition One, and you simply don't hear that criticism of 1911s.
I can deal with the USP decocker location more easily than a slide-mounted position. I can get to it with my thumb while maintaining the rest of my grip. Importantly, the pivot point of the USP decocker is pretty close to the second knuckle on my thumb, so the rotation of my thumb forward of that knuckle is naturally coordinated with the rotation of the decocker. The Beretta requires more of a reach that distorts my grip further, and the down-and-back rotation has to be activated with a fairly unnatural bending of the outermost segment of my thumb, rather than the more fluid "grasping" motion where the bending occurs at the second joint.
Of course, with the USP, you can also go LEM and avoid the decocker discussion altogether! I also really like third-gen S&Ws and Berettas in DAO.