Many people have already commented saying it’s good to go, but I also wanted to add, I have dug into their actual encrypted group messaging protocols a few years ago because I was interested in using it for a different use case, and I would say it’s pretty well thought out. I trust it, I use it daily, and I’ve looked at the code. I’m not, nor have I ever been, an auditor, but I have been paid to do cryptography and red teaming/cyber security from big orgs, so I would say I have some professional experience in the matter.