Well, like most others, if its your only bow and or one you value highly go with dacron for the peace of mind.
However, I have many older Bear bows that I use ff type strings on. The one I shoot the most, a 1961 Polar has a 450+ string on it. Have shot this bow at least 10,000 shots, and probably over twice that with no problems over a 6 yr period. Why? Well, it is about 6fps faster, the equivilent to shooting 4lb heavier bow, same string for 6 yrs never have to adjust bh, on this bow(not always the case with some others)it is just as quiet and "dead in the hand", did I mention its lasted 6yr.s.
This is just my experience for what its worth, and I have many other bows if this one ever breaks, you may not.
McK