Thank you very much for the useful information! I have signed up using the promo code and so far so good. The upload and download speeds are very good. They support WebDav, so I can use Cryptomator to encrypt my sensitive files from mobile devices.As far as I know they have been around for some years now.
Their data centers are in Germany and their office address is of Slovenia. Its good that they provide these infos.
They have also put up the names of their team members which is also a positive thing, but their LinkedIn IDs given on the page doesn't exist.
I would suggest you to go on with this, but as I always say 'do not keep any sensitive document on the cloud'.
P.S. - If you're not going to use it you can give it to me.