He'll be tough for sure General. He's a solid favorite. In his section of the draw, I only see a possibility of Tsonga or Karlovic troubling him, and I don't think Karlovic will make it to the quarterfinal with Berdych and Tsonga in the way. There might be a challenge from the other part of his half, in the Wawrinka/Rafa quarter but you never know how far Wawrinka is going to get, and Rafa isn't sure to go through on these courts.
Federer said in Basel that he was a little tired after the Goffin match after not playing much since the US Open, but then recovered a bit with Rafa, and said he felt ok. But I have a feeling he is saving himself for the World Tour Finals. I can't be sure of Murray, because he has been practicing on the clay for the Davis Cup final and I think his focus is there. Maybe Nishikori is feeling good enough to take that half, but you never know when he is going to break down. Ferrer is Ferrer. If he makes it to the quarterfinal and Federer is there, bye-bye Ferrer. But if Federer exits before that, he'll have his chances to make it to the final. He's won here before.
Respectfully,
masterclass