Agree with the guys`advice..... `Ventilation` refers to the way/direction hairs are attached/tied etc. into a base-material [Poly or lace] Freestyle is a particular `Ventilation` and is just that --``Free`` ..the hairs are tied in so that they don`t lie in any particular direction on a lace system...allows you to `play`with the style a bit more than you can with systems which have a particular/specific `Ventilation`style ..... go with French lace due to it`s durability...it will withstand a hard-hat far better than Swiss.