Frostbite
Periphery Shill
Jeez, a 49 seems way too thin for me. Even 10-52 is too thin for me, and I don't mind a bit of flop. I think 11-56 is perfect for Drop C and Drop B. I use 10-52 for Drop C#. But like I said, it a preference thing. All can work fine.
AFAIK He uses 10-52 in the studio and 11-56 while playing live for extra tuning stabilityI think Mark has stated in clinics in the past that he uses 11-56 for Drop C as well. That's how I roll with Drop C, tried 10-52 and didn't like it at all.