I like casting them all as well... the short belly spey lines are such useful lines, the mid-length are great all-around and the extended belly lines 90ft -105ft are relaxing once you get in the groove with them. They like a very s-l-o-w setup and and early forward stroke, long motions. Kinda fun but it takes a lot of room behind to make these casts.

Most of the time my favorites are the mid-length lines. They give you the best of both worlds.