Here is some additional floating line information that some people may find useful: http://www.tenkarausa.com/forum/view...php?f=4&t=3750
With respect to RIO's PowerFlex Core Shooting/Running Line used as a T-line, the Mono Core this line has makes it much more prone to kinking and coil set memory problems than the memory problems that the fabric cored PVC coated fly lines have. The Sage size 000 Wt. Double Taper fly line (which is also made by RIO) is another option for a possible floating T-line use but, it is pretty pricy now that Blue Ribbon Flies has exhausted their supply of their BRF Floating T-lines, and it does not cast much better than the level Rigs Floating T-lines do. With the Floating T-lines, I like a more conventional type of leader construction added to the line more or less as a permanent part of the line, starting with 2 feet or so of 12 Lb. test nylon mono, then 18" of 10 Lb. test nylon, then 12" of 8 Lb. test FC, then 6" of 6 Lb. test FC, to which 3 to 4 feet of 5 or 6X diameter FC tippet material is loop to looped on as the tipped and changed out as needed, then the fly of your choice. However, the leader can be of what ever design you prefer, and that casts the best for the types of flies that you are using, and under the conditions that you fish under.