I don't see how any pick can improve your picking technique other than one that is designed for that like the Stylus Pick.
The Stylus pick is based on forced accuracy which trains your hand to minimize digging into the strings when playing fast runs.
It is fool proof, and actually works.
If you alter your picking it will literally stop on the string.
So, to me, that is a good "tool" for training your right hand.
Gimme a Red Bear and about 2 hours on a 7 string, and I guarantee I will wear the pick down
But, I am no metal player.
The Ultex sharps are great for me, but they wear very fast too.
The only picks I have ever used that did not significantly wear are the glow in the dark alien face EBE picks.
But I kinda dig the sharps at $30 for 144 of them.
I don't loose picks, but hell, I would probably loose a Red Bear the day I got one.
I tried 5 of the V picks, and they just plain out sucked in my opinion.
I couldn't take the chirp that every one produced.
I need picks to go from heavy stuff to blues to funk strumming.
So, regular picks are what I will always use.