Race sails generally have a short competitive life if one wants to be at the top level. Many casual racers will get several seasons out of a sail, and in many cases the sail will still be serviceable, but not top-of-the line fast anymore.
Some of the non-dacron sails have a 'set shape' and do not react to normal tweaks of halyard tension and outhaul the way a conventional dacron sail might so in some respects can be less 'trim-able'...
Most real 'race' sails will not be as durable as a well made 'cruising sail'. Some of the materials used simply break down sooner.
All that said I quite like my 'no longer race worthy' pentex headsail. With no UV cover I remove it from the furler between sails, and appreciate its being half the weight of dacron. Some used race sails can be a great deal for a cruiser when that last nth degree of performance is less important. (I got a great deal on a used J-105 set that only needed jib recutting)
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"