I once had the same debate on the 18th as we were finishing.
I prefer them when they have that new feeling, as after a while they get a bit loose. So I took one of these worn but still usable gloves - FJ SciFLex and followed some web advice on how to clean with cold water and a little soap. After allowing it to dry I put it back in the bag to use on my next round.
After about 11 holes the index finger on my left hand was killing me. In short the leather felt thinner than normal and was a tad crispy 
. The elasticity of the glove was gone and it was binned on the 14th tee box.
