After reading the older thread, which I found most of the posts annoying and not convincing either way, and this thread, which tended to REFER to that thread as well as re-emphasize the same tired arguments, I think the points that JaJaWarrior and Diverrex make pretty much cover it. I eventually decided to try out the 3.0 SA. Yes, it's a tiny bottle. Yes, it's about as basic a regulator as you could possibly imagine and it's like trying to suck air through a long snorkel trying to breath on the SA at 80ft or better. But after working through a number of crafted scenarios, I find that I can indeed use it effectively as a CESA-assist at quite a depth. And it showed itself to be quite adequate to the paces I put it through at shallower depths. So, as with any other safety device, you have to simply KNOW what the limitations are, PRACTICE the use so that you won't use the device for that which it isn't suited for.
I dive conservatively and I simply don't run out of air. But, while too many of those posting seemed to completely miss the possibility of a catastrophic failure instead of sticking to the "just don't run out of air", I happen to be among those who believes Murphy's Law exists. While I recognize, and prepare for, the however slight possibility that I could find myself needing to come straight up (I'm more treatable on the surface than on the bottom, whatever the damage), I'm under no illusion that my SA is a silver bullet. I simply choose use Operation Risk Management. Because the chance of that kind of failure is so minute given my typical diving profile, it makes no sense to me to carry a full-on pony or wear a double, not in terms of expense, weight or hassle of carrying it. FOR ME it is purely a last-chance bailout option. I have proven to myself I can CESA from a good depth using it, and that's enough for me. I wouldn't advertise it as a great choice for newer divers for whom the CESA itself is a pretty unnerving thing.
So, people will irrationally hate something like the SA because they consider it a "pony-wannabe" that gives a false sense of security. Viral proponents will no doubt not like to admit they've probably never actually tried to use it in an emergency situation. Bottom line is know your gear, know YOUR limits, practice your skills and practice using all your emergency gear (e.g., how many have actually pulled out their signal sausage and used it?). Don't use things beyond their design or capability. Simple enough.