Blackstone was pretty much the first, going back to 1985, arguably the best in the field. There are others out there that are cheaper, but haven't been around as long.
The idea of using a spectrometer to see what elements are in the oil, and count the amounts of each isn't rocket science, but you're probably talking a difference of $5-10 dollars difference on a $30 total price, last time I checked. There's an abundance of information on their site.
Link:
https://www.blackstone-labs.com/information/articles/
Wix filters offers the service, Hot Shots Secret, the manufacturer of Frantz by pass oil filters offers it, plenty of places have the service available.
I believe it's useful, especially if you're trying for extended oil change intervals, without causing engine wear. The safest way to extend oil changes is with a by pass filter, and Blackstone covers the difference in standard oil filters, vs by pass filters on their site if you're going for extended oil changes.
Just curious of why you are considering using the service?