Don't think you're the only one. I don't normally post on this page... but I use full sinking lines. I use an intermediate, a type 2 and a type 4 sinking line. Can't say I prefer one over the other as they all have their specific uses.

The line that gets the least use is my sink tip.

The intermediate is a different one to use as it's like a floater, and one application is with flies near or in the surface film when it's windy and you don't like a belly in the line. The intermediate sinks and rides about 3-4 inches deep on the retrieve. It stays straight as the wind doesn't push at it.

Double hauling with the type 4 is nice for those times the flyfisher has a hankering for burying a hook point in the back of his head. (been there, done that, have the bandaid)