Hi John, I started using leadcore after attending one of Travis and Adriens salmon seminars at Fish and Game HQ. I took copious notes at the seminar as I had no idea where to begin. For mainline length, they said 30 ft gives enough distance from the leadcore but also is close enough so the oscillation of the leadcore puts action on the lure. I then use 8-10 feet of 6# Seagar leader material and have never changed the setup to try other combos. Clearly 100 ft works as your past experience shows but I imagine you lose some of the action from the leadcore. HOWEVER, you usually attach your leadcore to G2s so you have jigging action which probably makes up for and surpasses any benefit from lead core alone. Given that, the best part of the fight is when you get the leadcore back on the reel and are fighting them on mono/floro so that extra 70 ft is 70 feet of more fun. So I would say, if you are on the G2s with leadcore, stick with 100 feet and enjoy yourself. If you are off regular boards, go to 30 ft.