I use this picks only for bass playing and for that they're excellent. 2,0 millimetres is thick enough for bass strings and therefore these are my choice of picks when I need to play bass. For guitar playing these are, in my opinion, a way too thick. I've tried these with my electric guitar and I didn't like the way they felt or sounded. With acoustic guitar I haven't even tried. But for bass they are a good fit. One pick lasts long, because I've used same pick for about a one year now. Though, I don't play so much bass, but when I do I always use these picks.
I used to use thin picks, then experimented, I found 3mm a liitle too thick, but these 2mm I've used for years and theyre perfect and last longer than it takes to lose them! Buy them 10 at a time then you can leave a couple in every coat!! Strangely I always use the rounded end, not the point - i find I can get more "feel" and variety of tones!