Flew freight for a fairly long stretch (~6 years). Flew pax for a while, now fly air ambo.
Freight vs. the rest:
1) Pretty much ironclad schedule...you know when you're going to be at work and when you're not (this, of course, does not apply to nonsched, which I did for a while, too)
2) For the most part: Act, dress, and FLY how you want. Dog doo gets there on time, nothing gets bent, no one gets violated: no one cares
3) Work with "real" people. Most of the people you work with have got the t-shirt and aren't looking to impress anyone. Very low level of political nonsense.
4) (perhaps a subset of 3): Clear rules. No one second-guessing your wx or mx decisions (for the most part). You're the first and last word, which means that you don't have to share the sense of satisfaction in getting the job done.
5) Meet and hang out with some of the worst, most fun scum in the Galaxy. Prima Donnas get weeded out most ricky-tick.
Downsides:
1) Unless you're in a jet or in line for one, it can turn in to a bit of a dead end (provided it's not what you want to do for the rest of your life...obviously does not apply to the Big Boy freight ops)
2) You're going to scare yourself sooner or later. This is actually more of a positive, I've found, but it doesn't feel like it at the time.
3) The aforementioned bizzare nomadic back-side-of-the-clock lifestyle. Freight is not a job for gregarious sorts who need a close circle of friends with which to have dinner parties, etc. Luckily I'm a sociopath.
In total, I'd probably still be doing it if there were any stability whatsoever (speaking here of 135...121 seems stable enough). But it takes a certain Type.