HMPE - Fastflight or Spectra string material has been around for years.  It was first introduced after Dacron string material as it provided greater speed and less creep.

Compound bows in the 1980s - 2000s used Spectra or 652 from BCY - but it has now been replaced by materials with no stretch or creep such as 452X from BCY and 8125.

Today, 652 Spectra is still used on recurve bows as it reduces noise, and is faster than Dacron material.

Some Olympic archers are using new material for recurve shooting like the BCY 8125 because it provides more speed and less creep.  However, Korean archers have found 652 Spectra material more forgiving than the 8125 so Olympic archers are split on material for recurve shooting.  
European archers are largely shooting 8125 and Asian countries are using 652.

I have used both materials on my Win and Win Wiawis recurve.  The 8125 is much louder.  The 652 is almost silent.
I have shot my best scores with the BCY 652 material, but I am yet to test the difference over longer distances.
I am using BCY Halo serving as it provides less wear but cheaper serving material would also be suitable for recurve bows.

Steven
Archery Supplies