yes, i have the 'mud palms' fitted. there was one occasion in the caribbean where i rowed out my kedge about 30m in 2-3m of water (FX16 with 2m 6mm chain and 50m warp) then pulled in on the warp by hand to set it. i could feel no resistance at all and eventually it came into sight, gliding across the sea bed like a ray. a second attempt produced the same result. it was generally good holding ground and our Delta bower was holding fine.
Here is a tip to retrieving your Fortress or other anchor from our Safe Anchoring Guide web page:
"Slowly move the boat to a position directly over the anchor, pulling in the line as you go. Then snub the line on a cleat and power backwards slowly to pull the anchor out of the bottom.
Do not power forward because that will require more energy and put very heavy loads on the anchor and gear."