A properly sized "name brand" plow is probably (arguable) the best all around
anchor. That said, one of the two times mine has dragged was in a river off the Chesapeake when a thunderstorm came through at night. The river bottom was VERY soft mud and the plow just plowed through it. For those conditions, a "Danforth" type (I have a
Fortress) would have been best.
But my plow with an all chain
rode has been an extremely reliable
anchor over the years and up and down the East coast from Maine to the Caribbean.
The other time it dragged was in a harbor in the Bahamas that all the guide books advised taking a mooring in because of the extreme kelp conditions. But in my arrogance I thought I could get my
anchor to hold. I was wrong!