If you want to go to an academy, FSI is probably the way to go. It has been awhile since I checked, but the cost is about the same as the others, and they have several advantages.
1. Nice planes. Some are rather old (the Arrows used for Commercial SE and CFI) but they are all well maintained. And, they have a lot of them, so maintenance delays are usually not a problem.
2. Nice campus. If you are going to spend several years there, having decent facilities is a plus.
3. They pay their instructors a decent wage. When I was there I made $14 hr, and got full benefits (the insurance is very reasonable, at the time most of it was free if you were single, and even with my wife it was pretty cheap). However, like all flight schools, you only get paid if you are with a student, so if things are kind of slow, you can starve.
4. They don't lie to you. You will not see any ads guaranteeing you a job, and they will not try to swindle all of your money out of your bank account. If you want to leave, they give you your money without making you wait 30 days, or charging 'early withdraw' fees of several thousand dollars.
5. You get lots of multi-time. As an instructor, about half of the instruction is done in the Seminole.
There are also some disadvantages.
1. You might not get hired. No big supprise, but some times good people are not hired, and some that were not so good are. Go figure.
2. If you are hired, there is and endless stream of people who want to take your place and management knows it. I never saw anyone really get screwed, but sometimes the work environment was less than pleasant. You are there to be taken advantage of and to make them money.
3. It cost an insane amount of cash and after you leave, you will make crap wages at a regional for quite some time. If you have to borrow a significant amount of money, you will suffer for many years while you pay off your massive loan. A wife is helpful here (ignore looks and personality, wealth is the sole criteria).
It should be noted that the airlines are not the only way to go. FSI is probably best known in the professional world for simulator training. Students have the option of going to paid internships in various learning centers where you can get training and sim time. If you want to go this route, I would recommend going the internship route after being an instructor. You will get typed after a year (sometimes sooner, it depends on what center you go to). Ideally you would have ATP minimums or be close before going to an internship. If you pick a reasonable aircraft, (mid-sized) you can get a job that pays about double what the typical regional FO makes after the internship. At many centers, you can work close to full time and get paid $14 hr, so even during your internship you will make more than a regional FO. Not a bad deal.