if you have the times i would apply to xjt. If you dont have the time you will still need the mins to upgrade which will be hard to get if MX is cancelling a decent amount of flights due to teething problems, the weather in newark is crap, or the commute didnt work out. The new airplanes will have lots of little gremlins to be worked out and i have heard colgan works you pretty hard. xjt has a good contract and you wont be flying to the same 10 airports over and over again. Also are they going to have 4 day trips or mostly day trips? The lack of per diem could cut your paycheck by 500 bucks a month. the road to the majors isnt going to be made shorter at colgan you will just get treated a lot worse then any other company. This might be a stretch but go to CHQ or REP for the quick upgrade if you want to fly something larger then 50.
to the person who asked if xjet's class date can get you in quicker: they can but maybe not now. I interviewed on a wednesday and started monday but i have heard that they are slowing things down and putting people into a pool for two weeks now... just a thought.