I stumbled onto Blue Chip picks a few months back, and they're wonderful. I'll still use the Ultex, and even celluloid picks to create a few sounds, but for the most part these are the ones I constantly use. I have them in Jazz III and a slightly larger version with the Jazz tip.
It's hard to describe the sound, I've played tortoise picks before they became illegal, but without a back to back comparison I can't really say they sound exactly like tortoise. However that doesn't matter, the tone quality is incredible (clear and crisp high end, but full low mids and midrange, too), they don't slip out of your fingers, and they wear like iron. After 4-5 months of constant use I'm not seeing any wear.
For some reason the material is not slippery in your fingers, but it glides through the strings faster than other picks, and did I mention how nice they sound?
Yes, they're expensive. Yes, worth it (unless you lose picks, in which case, you'll burn through a lot of dough!). Monogrammed, natch. The material they're made from is some kind of unobtanium product I think, and it only comes in brown.
In fact, don't even try one, because you'll be hooked permanently. Pretend you didn't see this post.
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