Pros
Outstanding training and on-boarding process. Very well organized and safety-conscious. A great place for the driver who is new to trucking. Co-workers are friendly and helpful for the most part (a few grumpy souls, as anywhere, but they're fairly rare). Management seems to have its act together, and if you do too they'll treat you well and you can earn some pretty decent money. I was a total newbie, clueless driver, and they showed me how to do the job well - how to secure all types of loads, calculate placement on trailers, and so on and so on. There's actually quite a lot of technical detail involved in flatbed, and the people involved have to approach it as serious professionals - not your stereotypical truckers at all. Once I started solo, dispatch kept me working constantly. If you're prepared to go anywhere in the US and Canada, you can get huge mileage, and they'll start sending you all over the country - right away! They have lots of regular accounts, so as a trainee you get to know quite a lot of the repeat-business shippers and receivers, the layouts of their facilities, etc.
Cons
Just the usual for OTR trucking - lots of time away from home, nights in truck stops, and some hard work now and then tarping loads and moving trailer axles. If you can't handle getting sweaty, cold, dirty, and maybe a little frustrated once in a while, then it's not the job for you.