For pure memories sake, it would be Dollies, in AK creeks. I learned to drift before cast bugs on a fly rod. It was all egg patterns, and beads for Dollies, not bugs. You hit 'em hard when they follow the spawning Salmon runs up. But for entertainments sake, the most fun I've had on a afly rod, was smashing angry Coho. Steelhead fight like hell, but a Coho has that pure hatred about their actions. Getting dominated on 5 wts. is my idea of fun in a creek!