I've never used these before and decided to give them a try.  After playing a couple of different guitars using these, I think that I will enjoy them. They matched up very close to the same size and shape as the Fender flat picks when I compared them. The Tortex .88mm thick (green) pick seems a little stiffer than the Fender medium celluloid picks, but they also seem a little softer. They have a very slight surface texture that may help keep it where it belongs in my fingers. When playing my acoustic guitar, it seems that I get a slightly softer tone than with the medium celluloid, and I like it. UPDATE: I bought some of the .74 mm thick (yellow) picks and they are slightly more flexible than the green as expected. Very nice softer tone.