I'm considering a 4wt rod of 7' or 7.5' primarily for small stream mountain fishing. After reading the merits of both full-flex and mid-flex designs, I'm uncertain which way to go in the selection process. In the past, I simply fished with what I have and never thought about the flex design, but a good choice might make casting more enjoyable. Any rod choices and flex combination favored for the Smokies?