Agreed. Composition of the bottom makes all the difference. Mostly smaller rocks, gravel, and sand where I fish. Some of the rivers in Maine look like someone dumped in old headstones - big to huge, angular rocks that overlap, creating big, deep, anchor-eating pockets. Had a guide tell me he lost two anchors in one trip on the West Branch of the Penobscot. Every guide I have fished with there carries a spare.Personally I'd be cautious with odd shapes as it would be a nightmare to get it caught up under a rock after it slides on the bottom while trying to hold in current.