I can only speak for the Gulf Air side of things. Overall it's not a bad place to work, especially on the Boeing fleet (there have been a few troubles with odd individuals on the airbus fleet, especially if you're american, but most guys are good regardless of fleet. It only takes one or two idiots making your life miserable before it becomes unpleasant though). They treat pilots well compared to western standards, the pay is exactly what they say in your contract and always ontime. The joining procedure is a bit disorganized, but you can muddle through it. BAH is a decent place to live, it's small so you avoid alot of the bigger city issues, though it can be boring if you're stuck at home doing nothing. You won't be able to sponsor a girlfriend in here, you'll have to marry her to get her in on your visa. That being said depending on where you're from she can come in on a visit visa for 2 months or so and then leave for a day and come back again on a new visit visa.
Biggest issues at GF are housing/school allowances are not realistic, and rostering sucks with no real bid system and lots of changes during the month. If you are single, or married without kids or any significant bills you can save money as an F/O. If you have kids that need to go to school you can scrape by and that's about it.
The pass system is rather expensive and restrictive compared to a major international carrier, but you can still get pretty near anywhere in the worldyou need to go. Friends/family is another story though.
All of the airlines here have there own set of problems so pick your poison. At the end of the day you can have a decent lifestyle in BAH and leave work behind when you go home it's quite pleasant.