If you like being a number, then these schools are where to go.
If you like personal attention, avoid like the plague.
Yes, these schools are good at the overall image, especially like Gone West said for after market training ie types, however the time to complete if often far longer, the scheduling very inflexible, and the groundschool goes only as fast as the slowest person.
In my class I had a person for CFI that had not flown in 25 years; I slept most of the course having just passed my Commercial, as we reviewed the basic basics! Not time either my colleagues or myself would have chosen! We would have preferred to spend the extra time on more challenging items! Passed first time mind, but could have got the same time and ground elsewhere for a great deal less spent on accommodation and ground. The problem is the rigidity of the course. The big schools are not flexible!