The FIRST method has been proven successful. I read their book a few months back, it delves a little more into the science behind their program. I think you'll have success with it. I think the biggest hurdle they have to overcome in order for their program to become more trusted is the mentality amongst us weekend warriors that more running=better running. Numerous studies are showing that's not necessarily the case.
I'm sure you've already seen their web site, but if not, the address is
http://www.furman.edu/first/index.htm Some of their other programs are outlined on the web site. I would recommend you read the book, too. It's called "Run Less, Run Faster". The biggest thing to remember is that with their program, proper pacing is crucial.
I think I posted a while back that a friend of mine qualified for Boston using the FIRST method, and running only on a treadmill. It has worked well for a lot of people.