I've one and it's very generous for a "free" email to be honest.
1GB, unlimited aliases.
However I've the same fear that @nosim mentioned above, that I've seen some people being locked out of their accounts (which I believe they have violated the t&c) so I'm hesitant to use it as my primary. The same can be said on Tuta free account too, I've seen more than several reports that their free account was locked out of nowhere without warning so I would be cautious with Tuta as well.
Disclaimer: I don't have any spare invites so please don't ask for one from me
