I think it's a good idea, especially if you've recently passed SRM.
* From what I understand, SRM provides a great foundation for PA. I have also heard that you don't need to study for PA as much as you need to for the other prelims (although it still requires a month or two of intensive study).
* FAM-L is a 1.75 hour 20 question multiple-choice exam, so it won't require as much studying as a full-length exam would.
The only reason I don't plan to do this is because I've been slacking on my modules. I really need to muster up the willpower to get through those...