I'd say not unusable for an occasional link, but for generic browsing sessions, I wouldn't use it because of the absence of adequate build-in privacy, like blocking third party cookies, but also the lack of add-on support. The current web is just too full of tracking dreck. On both desktop and mobile I use first party isolation, http smart referer header, uBlock origin in an aggressive mode, cookie autodelete and I don't care about cookies (because they are thrown away anyway). A pleasant side effect is that I rarely see ads, and when I do, they are harmless because of all other measurements - I might even click on them.

Yes, I'm aware of some hosts-based (ad) filtering options on SFOS, but that is just part of the story.