I like all aspects of GT in general, but most importantly how easy it is to use! The interface itself can be overwhelming at first for new users looking around trying figure out what everything does- however their support team are always more than willing/able assist you with any questions (which we have had only very rarely).
We primarily used this software when sharing large file sets between 3rd party contractors during construction - and as such there were thousands upon thousand's per project which needed tracking & storing securely online using cloud storage services rather then email attachments etc.- Which was easily achieved by going through Google Drive instead?