David Guetta can remix just about anybody, but few have what it takes to return the favour. Kings of big-room boom like Afrojack and Laidback Luke, trance man Armin van Buuren and Swedish house prince Alesso are among those brave enough to take on the French don's anthemic dance pop, adding new synth layers and stadium-filling bounce to stratospheric floor-fillers voiced by Sia and Rihanna.