Victor,
Great post.....are those flies you tied? Nice work. I have used the Mushmouth (gray and white) fishing for speckled trout (caught in the bays of the gulf coast in the U.S.) and I used the pattern with success recently in Australia. The great thing about it is that the fly is very versitle.
For tuna I know people who fish it on a sinking line with good results, and I was using it for sightcasting to barramundi and golden trevally (kuwe mas?) The buoyancy of the fly and "soft landing" when cast made it perfect to sightcast to the barramundi with and aviod spooking them. The guide (Nat Bromhead from Australia, based out of Hervey Bay Nat Bromhead's Saltwater Fly Fishing Adventures ) I was with liked the pattern so much I left him with one so he could copy it. He is going to tie some up to use on Marlin in Australia!

Do you know a source (internet) where you can buy the materials? Which is the best material you have used for the fly....the ones I have are very shiny and I think are unique hair or slinky fiber....?