I have been trying to get the facts on the reasons for using 4oz warp or basic 6oz cloth. Strangely, from all enquiries I have made, 4oz seems to have so many benefits over 6oz apart from being slightly more expensive that I am suprised that 6oz is used at all. I am comparing a basic 6oz hexcel cloth to the 4oz warp cloth since I these are the ones that I have experimented with. Please correct me if I am wrong Weight after lam - 4oz warp lighter (absorbs less resin) Additional weight from hotcoat - 4oz warp(smaller weave, less resin to cover it) Tensile Strength along length of board - 4oz warp(more length weave strands) Impact Strength??? Ease of use - 4oz (ok 6oz does hold it's shape a little better and tends to fray less easily but I find it much easier to laminate with the 4oz because you don't have to worry as much about working out Price - basic 6oz wins Apparently 6oz warp is not used that much in surfboard building since it is difficult to work with? One more q! How many alternative quality brands are the out there other than Hexcel. I know that Rusty doesn't use Hexcel which I previously thought was the el primo of cloth.