Pros
You get to travel and see a lot of neat things and meet some weird people. You can learn quite a bit if you've never done this kind of work. They take great care of anyone with a white hat or higher.
Cons
They say they have competitive pay but you're lucky to get $16/h and you will never see the raise that is promised. They only give you $35/day for per diem. They make a lot of promises for great things and pretend like they're trying to help you but after you get hired on everything gets shot down and your hopes and dreams will be crushed. Any time you need a tool or anything else at all it will take you a year to get it. Everyone complains about everything and a lot of them don't like to work as a team. When they send you out of town expect to use your own gas because they like to let people take the company trucks to the close. So if someone has to work an hour away from the shop and you have to work 6 hours from the shop, odds are they will get the truck. All their tools are crap and they don't like to buy decent ones. If you don't have a white hat you have no rights. Pay will suck, no one will even consider a word you say.