Easy killer!!! I've done 121, 135, and now am at a 91 gig. I was a better pilot when I flew 85 hrs a month than I am now that I fly 25 hrs a month. Personally I think it's all about the individual regarding customer service which is what 91 guys are supposed to have over a 121 guy. I call bs on that myself. If flown with great guys in all three areas. As well as d-bags in all three.