The L-500C is much cleaner than a P-90, and the output is higher, too. The designs are very different; a good P-90 has the tonal hallmark of a fat single coil, while the L-500C is a full blown humbucker, but with a very clean top end response.
IMO it's a great neck pickup for basswood, spruce or lightweight mahogany/korina bodies, without regard to musical styles.