They don't give that "click" sound like a plastic, nylon or other pick. I have compared them to tortoise, weg*n, and even Bl*e Ch*p, and they sound so close the same, it was a surprise. With Tortex and the 3 others I listed, you don't hear the sound of the pick, only the sound of the strings. Tortex is cheaper than the others listed so what's the best buy? Also for those who say sweaty finger make it hard to hold on to the pick, I've got a proven solution. Lay a dime in the center of your pick and take a pencil and draw around the dime. Take a 1/8" drill bit and drill one hole in the center of the dime pattern, then 1between that hole and the line you drew around the dime, then continue to drill approx. every 1/8". this doesn't weaken the pick and you've got grippers. Use a drillbit for the holes and it looks neater and your pick won't break where the holes are. Some people I know of have used "Gorilla Snot" and it works. You only need to touch your finger in the "snot" though, or you will be able to de-lint your black britches.
ProsThis pick gives you more of the pure sound of the strings and a lot less of the click you hear in cheaper picks. I've tried most everything on the market and these are among the best, only a lot cheaper.
ConsThey get slick in sweaty hands if you don't drill some gripper holes.