Lotech,
A lot depends on the type of flyfishing you do on what leader would work for you. A very limp mono line probably would not turn over your flies. I cannot tell you what to use, but, I can tell you what I use and you will probably get better responses from the others on this great board.
When I am fishing I will be using a nymph about 98% of the time. I started out with tapered leaders and, like you, decided that they were not for me. I switched to using straight fluorocarbon in 6 pound test. I would use about 9 foot of it and tie my fly to the end of it. It did a fair job of turning over my nymphs and the fish did not seem to mind and were cooperative. I then decided to order Kathy Scott's DVD on how to make your own furled leaders. I now make my own furled leaders about 7 foot long and attach another 5 foot of 4 or 6 pound test fluorocarbon on the end of it for my tippet. Everything is a loop to loop connection and when the 5 foot of tippet gets a little short, I just remove it and add another 5 foot piece. Everything turns over great and I will never switch to anything else. I make my furled leaders from Kevlar tying thread and 4 pound test Berkley Vanish Fluorocarbon in the green color. They both sink and for a nymph fisherman, that is what I want. If you do a lot of dry fly fishing, you could make your furled leaders from 6/0 tying thread and treat them with floatant and they work real well. It takes about 20 yards of material to make a 7 foot leader and there are a lot of furled leaders in a 250 yard spool of Berkley Vanish or a 200 yard spool of tying thread. That is what works for me. You will just have to see what works for you and your style of flyfishing. I feel confident you will recieve better advise from the others on this board. Good luck.
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Warren
Warren
Fly fishing and fly tying are two things that I do, and when I am doing them, they are the only 2 things I think about. They clear my mind.