I used it since a few years before Google bought GrandCentral in '07. A couple of years ago I moved to voip.ms as part of my de-googling and am happy with it. There are oodles of such providers.

Oodles of providers that give you a permanent US number for free?

I didn't look for a free option after leaving Google Voice. I'm happy to pay the low cost to be the customer instead of the product. Same with gmail to fastmail.