Saddles, argggh!
Like many, my saddle journey looks like this: Bontrager butt-hammer, Alias > Toupe > Prologo Scratch > Antares > new Toupe > and now a Regal.
Funny thing is, I used the Toupe the most, wore it out, and about that time it hurt like you described (intense sit-bone pain). Tried a bunch of others, even a new toupe, but am having the most luck (e.g., the least pain) on the Regal.
I'm convinced some have an iron butt, or are just lucky in finding what works. Remember, it's not only the saddle itself, but how you set it up, what bibs/chamois you're using, use of chamois cream, types of riding, fitness, phases of the moon, whatever...
Keep looking, there's bound to be the perfect saddle for you.