I have it on both my boat currently. Its pretty good. I have found it to be slightly less durable than the 8oz it replaced. To fix that, I put a keel strip of another layer of fabric. I cut the strips up (I would recommend melting the edges) and soaked them in a cup of poly. I then layered them over the keel, brushed out the air bubbles and let it dry. Another layer of poly fused everything together. Wood keel strips cover the bow and stern.
As far as the workability of it, the lighter weight fabrics are going to be more workable than the heavier weight fabrics.
Never used cotton, so I can't comment on that.
Scott