There are many options out there right now to deal with the fuel system of our 24-valve trucks. Many have had very good luck with everything from relocating the factory lift pump close to the tank, adding a pusher pump, or a complete system such as the FASS, Air Dog, and RASP. All options have their pros and cons. In your case, spend some time becoming familiar with each and decide what will be most appropriate for your current and future plans for your truck.
As far as the FASS goes, I have been more than happy with mine. In fact, most of my friends here are running them now and they have performed very well. So, would I buy the product again... absolutely.
Again, most all of the systems out there now are very high quality units. Take some time to get acquainted with the features of each. If you have any specific questions, let me know.
Justin