I mostly just don’t see the point in them. If the technology could run a live adblocker that would be a different story.

Yeah, as long as it’s not Google, it works. The real trick is to find a good email aliasing service (I use Addy.io) so when email are exposed in a data breach you can just turn it off and avoid spam. Also good for when your trying different emails out because you just have to update what the aliases send to.

I use Posteo, honestly I don’t think it matters much what you choose, anything will be better than Google, encryption is nice but only works if both people have it. Your emails will be as secure as the other address.