That seems weird to me, thirteen. I started out on glowsticks with shoelaces, and I can easily do spiral wraps and infinite spiral wraps (or nevisouls, don't know if there's an agreed upon name) with my flowlights, but my sock poi keep stretching and desynchronising just before I twist my hands to bounce the poi out again.
Back onto isolations, started learning them recently, and I feel that it's actually the way the sock poi stretch that make them more forgiving when I'm trying to isolate, in addition to them being quite a bit heavier than my crystal poi.