The Bosnia international, 27, has spent almost his entire career in the UK since joining Portsmouth in 2005 so is well-versed to comment on the qualities of the game in this particular region.
"I can't speak too much for other league's because I've only ever played in England myself, but every aspect of your game will get tested here," he told the Daily Mail.
"Whether it is your shot stopping, your cross taking, your distribution, communication or organising; every aspect of your game will get challenged.
"England will test a goalkeeper to the max, so if you play here you are one of the best in the world.
"Sometimes in Spain or other countries it's focused on 'one-vs-ones' or distribution because you don't get too many high balls into the box or Marouane Fellaini charging in at you."