yes they do work well but they are difficult to cast with, we experimented with many different shapes in the 70s and even make boilie cakes although the word boilie hadnt been coined in those day, but sometimes inconsistent shapes do work, for distant work use a bait boat, its always worth trying something different of course, but remember the carp may not be use to it and may need time to recognise the food sourcse, having said that we used luncheon meat for years and its still very effective as a bait, round boilies though as more convienient