I pretty new to the APMC and to the forums. This just a very novice opinion so please talk to others as well.
The APMC has its good and bad points. It really depends on what you want from your experience.
I was sold the same story as you are. I am still happy with my decision to join the army but still not certain about the APMC.
The recruiter is right that you do get a lot of flexibility for your drills. The down side is that you are responsible to set them up. For me this has meant calling units and begging to drill with them. Lots of phone calls to the VA and Army hospitals( still no luck with them) and even doing recruiting activities. I have had to become very creative some months to get my time in. The other problem is that most facilities only function M-F which means you may have to miss work to get your drills. Most reserve units instead will drill on the weekends. The downside to being assigned to a unit is that you are stuck on their schedule.
To be successful in the APMC it helps to have prior military experience or contacts to help you navigate the intracacies of the military. You are assigned managers to help you but they are hit/miss on the helping part. The managers are also normally overworked and are normally back logged. In a unit you may have a better luck with getting administative help, at least you would be more than just a number.
In the APMC you are still required to do 14 days of active duty each year. Your 2 weeks can be done lots of different ways, which can be good or bad. You still must join your assigned unit every other year.
I don't know if this is true but it seems like it is harder to get through promotion process in the APMC. This is mainly due to difficulty getting OERs. Also you are mainly on your own to get your files complete.
In the end I enjoy the fellowship that a reserve units has. Although the reseverve units have welcomed me when I drill, I never feel like I belong. I joined the army to do more than just pay off my loans. I am now begining to consider getting assigned to a unit instead of the APMC. Hope this helps