Originally Posted by SteveI
The price might be the same.. they play nothing alike. Polylon is really bottom of the market. Really only works for a small group of players and is hard on the arm.. where as the IsoSpeed is much softer and has nice touch and feel. I have played both strings a ton. Depends on what you like.. but as other have said.. matching Polylon with a stiff frame is not a great option.
Polylon also losses tension like no other poly I have used. It is of course, very much 1st gen stuff.
I have some Isospeed Pulse that TW ranked very high for a poly in the softness/arm friendly category. I'm looking forward to stringing it in my 99S's when they come in.