These are awesome picks. They do take a bit of getting used to because they are much stiffer than a traditional cellulose or plastic pick. With that said, they're my new favorite for all of my guitars. The stiffness combined with a pointy profile like a jazz pick gives me a new level of control in my picking. Although they're stiff, the material has a natural quality that makes them slide off the strings with less effort. They cost more but they really do last many times longer and the performance is far superior. Many old timers talk about the sound of tortoise shell on acoustics - deeper, richer with more attack. These sound amazing when compared to ordinary picks on my acoustics. Bluegrass guys will LOVE these. I've recently started using them on my electrics, too. Strong attack when I need it but it's easy to control. Highly recommended. I really don't use anything else now.

I've been trying out different pick materials - bone, coconut hull, and others - to get different tones from my acoustics. It seems that Clayton and Fndr each make picks from a protein composite that simulates tortoise shell. My personal fave is the Clayton NuTone. These really give me the tone I was looking for and they have a shape that works for me.