Advance warning, I've drifted some from the OP's question, but I do have the experience he wants.
I've been training since 1999, have moved around the country a bit, and have trained at lots of places. I've done sport, MMA-centered stuff, and recently spent some years at a GJJ place. I'm not convinced that most GJJ guys will actually handle themselves any better than someone who trains anywhere else. Staying calm and knowing how to use your body (and your opponent's) goes a long way towards being safe, instead of specific "self-defense" techniques. Going beyond that, what I think that I'm seeing in the GJJ world is the very thing that we all used to make fun of: lots of kata-like drills, deference to a picture on the wall, and lots of excuses if anyone gets beat by something that's not in Helio's "Master Text." In my experience from a few GJJ schools, you will often hear something along the lines of, "Well yeah, you're able to hit me during this drill, but an unskilled person wouldn't be able to." I want my stuff to have a chance to work on everyone, not just unskilled guys.
I've trained with a number of R. Gracies, and the Renzo quote above is apt. You'll find lots of tough GJJ guys that will impress on the mat, and I suspect in a self-defense situation (though like I said, I'm unconvinced that it's actually any better than what the rest of us are doing), but by the very name of GJJ, they have painted themselves into a corner, I think. My experience is that if Helio didn't do it, they're generally not going to be doing it. Renzo, like lots of us, adopts new best practices when they are offered to him.
For the last year or two I've been thinking about it like this: Imagine watching footage of a particular sport from the '70s, and watching footage of that same sport today. The old stuff absolutely works, it was using best practices at the time, and there is a technical proficiency and beauty to it. However, we've moved on, adopted new best practices, and are learning new stuff all the time.
Apologies for ranting!
tl/dr: Longtime practitioner with experience at many places thinks that GJJ is fine for self-defense, but everyone else who trains will be just as fine.