I've been using Spideroak https://spideroak.com/ https://spideroak.com/, they push security but only have 2G of free storage and their prices are steeper. But

I've been using Spideroak https://spideroak.com/ https://spideroak.com/, they push security but only have 2G of free storage and their prices are steeper. But they have a Linux client! Proprietary, but I can never get grive to work right so I use it (hesitantly). Most of my stuff is synced via owncloud, though.