I am a recent graduate of the ATP ACPP program. There are lots of Pro's and Con's to going to ATP and I will list a few as this might help lead you to the right decision.
1.) If you are ok with studying on your own and only getting lessons when you ask your instructor a question ATP is not for you. They do offer digital ground schools now but keep in mind some locations have 2 instructors and 8 students so the instructor isn't always around.
2.) If you are looking to get your rating fast you can do it provided you work hard. I completed the entire program (I didn't get my CFI's because I disagree with how they teach that program) but I finished ME PPL-both commercials in a little over a month. Me and my instructor flew more than any one else but I had all my knowledge test done and I had a few years to study when I was in the military.
3.) The whole we promise you a job deal is gone. In fact, ATP is currently using that scheme to get students to enter their brand new SE ACPP track where they will pay for your ME ratings. OK I don't see them hiring for a while so there's just one of few of ATP's empty promises. All the instructors were hired knowing they were guaranteed a job for six months yet there are instructors who have been there for years.
4.) I wouldn't want to work for that company. I trained at JAX and they treat the instructors like crap. Bottom line you will work like a slave for very little money (which is all part of paying your dues) however, there were several instances where my instructor was reprimanded because the DPE didn't like the way he taught me something. For example, on my IRA check ride I hit one more button to load an approach than needed because I didn't know the short cut and that almost cost him his job believe it or not (no that wasn't made up either).
5.) Trust me if you go over flight time you are paying for it. You are buying a very strict set flight time for that tuition. If you need to more flights to get you to solo guess what if you aren't paying for it they will start taking flight time from other areas. On the flip side if they owe you flight time they will make an excuse not to pay you that money. I used 6 out of my 14 hours I was allotted for the CSEL. You think I ever got refunded that money. Sure didn't because I originally elected to do CFI school but later changed my mind when I found employment at a sky diving place that later didn't turn into fruition when I lost my medical with a problem that was never discovered.
Now to make myself perfectly clear I am not pro or anti ATP I simply disagree with a lot of the empty promises they make to young "kids" that later get screwed in life. I was probably the only one that didn't go in there thinking ATP was going to call me a week after I graduated saying congrats bud your hired. I did my research and I asked all the right questions and I had no intentions of ever instructing there. Again for as little as they pay you I've never seen a company treat it's instructor's like crap. They get away with it because guys simply need to build time so they will tolerate it. The instructors could fly good, most knew their stuff, and to an extent the program was as advertised. I don't regret my decision to go there but certainly wouldn't lead any of my friends to kick down the front door.