They're through The Good Feet Store and called Gait Enhancement Technology orthotics (they're the black ones). These ones are specifically maintainers and used by athletes. You need to be custom fitted for them.
https://www.goodfeet.com/
Just a heads up however, some salespeople there are more knowledgable than others. You'd think that everyone has the same level of experience selling these orthotics, but that's unfortunately not the case. I think that's where the complaints online originate from. An educated salesperson will observe gait changes, changes in balance and the sound your feet make as you walk. If you have even the slightest hesitation with a particular fitting, then have them start over (or ask for someone to help consult).
If we're strictly talking about hiking and high-milage, then you wouldn't want their strengtheners anyway because they start to get a little uncomfortable after 5-6 miles. It also helps to bring your hiking shoes/boots and the socks you're going to use while hiking. If everything else is already dialed in, then these orthotics will probably just make you smile every time you put on your footware. I've been going back once a year for replacements and adjustments, which is a nominal fee (and make sure you get this in writing so the price doesn't change).
I've been getting around 1000 miles out of them before a replacement is needed. They're plastic and eventually wear out, which is expected. But think about it. Superfeet are around 60 bucks and last about 500 miles with hard use (the Superfeet warranty is actually 12 months or 500 miles). They push these inserts at REI like crack. But the foam on the Superfeet is also "super" flimsy.
These are $500, but I pay 20 bucks for a replacement (the price for replacements may have gone up slightly) and I have yet to change the full-length insert (which is optional but helps...but you can also use thin yoga mat if you're on a budget). So, I'll save 80 bucks every 1000 miles (until I need a new insert). If you're not planning on cashing in your life insurance policy anytime soon, then these could be a great long-term investment.
What works for one person however may not work for another. Everyone has different needs. I unfortunately now have hundreds of dollars of insoles in my closet that I'll never use again because my feet are spoiled.
This was a much longer answer to your question than I expected to write, but I've tried almost everything including Z-Coils (which are mostly a gimmick unless you have serious issues).