Re: What type of leader do you use?
If there was; "All of the above" I would have checked that.
I tie my own mono leaders for trout fishing with my graphite rods and use both furled thread and mono leaders on my 7' 4wt boo. Joni's mono furled leader is a great leader.
I do use commercial leaders but only on occasion. I keep a few in my vest when trout fishing, just in case. I do use a 7 1/2' 3x commerical leader when fishing for bluegills. I don't know why but I do.