I use primarily WF lines. The reason; I fish some streams and rivers that are wider than my casting distance, and those streams and rivers typically have some high winds. When I fish lakes, I also prefer WF lines because it's typically tough to sneak up on a rising fish so I need longer casts. When I'm trolling behind my pontoon, it's easier to cast most of the distance needed to get to the required depth to troll, rather than feed line out by hand.