Well, the amount of research I did has been greatly exaggerated!
And I'm afraid I don't know anything about Primera Stone. So we'll have to look to others about that particular finish.
I determined, when I was shopping, that the pebble I ended up with would last much longer than plain plaster. That's about it. The pebble was considerably rougher on the skin than my old plaster. So that was the tradeoff. I realized that if I chose any finish that wouldn't last longer than me, than the next plaster redo would be considerably more expensive, and that was before all the shortages, inflation and price gouging going on. So all I can suggest is that you find the longest lasting finish you can afford, that feels OK on your skin, and go with that.
Now the problem with that is that there aren't too many surfaces claiming very long life that have actually been around that long, so how is one to know? You don't. You talk to multiple
installers (not just those that sell the stuff), and research the 'net, as you are doing, and try to find some sort of consensus.
Now, if this is not going to be your forever home, and you'll be in it less that 15 years, then don't sweat this. Get a finish that is affordable and that feels great. Because the finish you install, no matter what it costs, or how long it claims to lasts, will not help the resale value of your home one bit. Most buyers won't even think to ask about your finish, or how many more years it has left. And home inspectors are not qualified to guesstimate that, at all, so they don't. You buyers will be happy to have a pool and won't know the difference about the finish. And even if they did, they wouldn't offer you more because they might think it'll last 10 more years rather than 5. Real estate value doesn't work like that.
The only other thing I can advise is to try to see the various choices live. I was lucky enough to have a showroom within a few hours of me that had dozens of surfaces I could actually see and touch, like in a pool. They had about a half-dozen pools and each pool was finished in multiple surfaces, like a quilt, so I got in and felt them all. Which, if you can find something similar, I highly recommend. What I did wrong on that account was how I felt each surface. I got in knee deep to feel with my feet, and I rubbed them all with my hands. But that's all I did and that was a mistake. The skin on your hands and feet is the toughest you have. When I got what I thought was "smooth enough" in my pool, and then got in, I realized what I had missed. The skin on elbows and knees and, pardon me, tushes, is considerably more tender. So when I am kneeling on my finish, or sitting on it, or have my back to it, it's rougher that I would like. So if you are lucky enough to see these finishes in person, get in and really "torture test" them and feel them with as many body parts as you can. I know that sounds silly, but if you are lucky in finding a 27+ year finish, you're going to have to live with it for 27+ years, so be sure it's going to be something you love to look at and touch.
That all said, the single best thing you can do to extend the life of a pool finish is to hang out here. Your water's chemistry, more than anything, will determine how long it will last. A pampered plaster finish can easily outlast a neglected "25-year" finish. Stick around, learn how we take care of pool water, and that'll add at least 10 years to your finish over relying on pool stores or pool guys to take care of the chemistry.
And lastly, beware of warranty promises. The warranty is only as good as the company lasts. If you get a warranty from a big, name brand, that'll increase your chances. But a warranty only from a local installer will expire when his business does.
Sorry I couldn't be of more help...