I think bieber wait till the doctors say he can't preform on sziget! Don't forget its a lot money and his agency will do anything so he can come to sziget.
Yes the line up for the q dance takeover so far! I don't know how many more to suspect but i think it will be a nightparty in te party arena so maybe 1 or 2 djs more.
The budapest card is a lot expensiver!
You can just buy a 7 day card
https://bkk.hu/en/tickets-and-passes/prices/travelcards-valid-for-one-or-more-days/