I play professionally, typically 2-3 hours per show, several times per week. I play an acoustic guitar very loudly, unamplified. I use this pick to get a good tone and good volume, and it's a wonderful thickness and curve. The only problem is that after perhaps 5 hours of playing, the tip wears down and I must get a new one.
This pick is great -- if you play super loud / often, purchase many of these and discard the old ones, or look for another pick material. ;)