Simon Cowell travels to X Factor auditions in a tour bus worth almost R17-million.

The music mogul – who left the UK pop star search show to focus on setting up the US version – uses the 1200 sq ft vehicle, valued at $2-million, which has two bedrooms and two bathrooms, to tour America for auditions.

According to Radar Online, it also has a $150 000 mobile medical unit.

The vehicle – which also has a kitchen, green room and a huge cinema screen – costs $9000 a week to run.

Cowell is hoping the Fox show will wow viewers when it returns for a second series, after he replaced judges Paula Abdul and Nicole Scherzinger with Britney Spears and Demi Lovato.

Britney recently revealed she is having a "lot of fun" working with Demi, Simon and L.A. Reid and tries to be constructive in her advice for the contestants.

She said in a new promo clip for the show: "So far everything has been so fun for all of us.

"Everything is like a new experience for me, so it's a lot of fun and the talent has been amazing.

"I feel like my judging style is very subtle. I try to use constructive criticism."

Despite saying she is "subtle", Spears - who has been described as an "incredibly tough" judge - is seen in the video dispensing some harsh words to one contestant.

She tells the hopeful: "I wanna know who let you on stage."

The X Factor will return to Fox on Thursday, 13 September.