What you get in AA are AA miles. They are no different (for award purposes) than any other miles. That is, the expiration is the same, the use is the same, etc. So, for example, if you deposit 120,000 miles you can use them for 3 plan ahead domestic first, or 4 plan ahead domestic coach (with 20,000 left over) or whatever else you can do with 120,000 miles.