They are a very well known and widely used brand for home installs. Like most companies, they make some good products and some less good products. I have used them from time to time. I wouldn't have used them if I didn't think they were good speakers. (Though I also wouldn't have bought them for myself, but then I am really difficult to please, especially when I'm spending money.)
For the homeowner, they can offer good sound and build quality, if you choose the right speakers. They also offer a full line of speakers, and seem likely to be around forever, which means service, repair, replacement, additional speakers, etc. will be available down the line. Those are important considerations. Though of course other companies offer that as well.
If you want the absolute best sound, then you need to do more work. Though lots of people say they do, but really don't, or won't pay for it.
For the installer, they are a line that is not typically available to consumers directly, although that is changing. That means they don't have to compete with Amazon or Best Buy, and can make enough money to cover the complexities of the install. Consumers are often reluctant to just pay the cost of the install, the way they would with an electrician or a plumber. I guess because they think they can do it themselves. So the AV installer tries to sell speakers and other gear that they can make a margin on.
You could learn a tremendous amount by doing a Google search.
As always, the bottom line is whether the installer is capable and can be trusted. If you can find out - ideally references from people you know (and that can be the general contractor if you trust them and they have real experience with the AV sub) - that's the most important thing to know. Funny how it always comes back to that, eh?