After a very long period of invite system closed, TTG opened its invite system during its latest happy birthday event a few weeks ago (all previous invites had been cleared, users must buy invites from stores for 100k points per invite). As far as I can remember, it opened for 1 day.
Honestly, TTG is special to Chinese users, I mean very special to Chinese users only, but nothing very special from it if we aren't Chinese. For Chinese users, TTG is 10/10 together with M-team because they have a large base of torrents which include: movies, TVShows,...; and because speed among Chinese users is better than foreign peers. Old torrents seeding is not so good in terms of seeders.