With something like a 4/0 Flashtail Whistler or Deceiver, 70-80 feet in calm conditions from the deck of a boat with either the Tarpon intermediate for Tropical Floating Clouser line. Line is stripped into a Flyline Tamer with an inch or so of water in the bottom. Less distance as the wind picks up - but still 50-60 feet into a good breeze if I needed to. With the Intermediate Tarpon I had to strip it in quite a ways then roll it to the surface to pick up and recast if I let it sink at all. With the floating line I could pick up about 40-45 feet of line with a big fly (essentially the entire head of the line), more with smaller, lighter flies, less with a heavily weighted one like a 3/0 or 4/0 Clouser Minnow that had a chance to sink. Most of my actual fishing casts with these lines were in the 40-60 foot range - I didn't need to reach out farther than that while actually fishing. The lines shoot really well.