I have just replaced my two venerable 16kg Delta anchors with a Fortress FX11 that fits nicely in the moulded recess and a Knox 13kg that fits ever so well over the bow chain slot. I know that new generation anchors can be difficult to fit nicely on bow rollers so I thought I would share this. I am impressed with the quality and workmanship of the Knox but have not had the chance try try it out in testing conditions.