I use a 9ft 9 weight for muskies but prefer my 9ft 10wt. Most of my musky flies are large, e.g. 8-12 inches long but I also throw quite a few in the 6-8 inch range too. I try to tie them out of relatively light materials and although I have tied some huge deer hair musky flies I find them difficult to throw even with the 10 wt. This could be a result of my casting abilities as much as the size of the fly however.

Rick