What dictates what line I use is several factors. How much wieght I will be using and size of baits (current). What the reel is rated for (I may go to braid on a reel rated for say 14lb test mono, go to 65lb braid that is aprox 14 diameter) That way I dont jeapordize the amount of line capacity. If I need more casting distance, go to smaller mono or equiv diameter braid. What size fish I expect to POSSIBLY catch. Amount of structure Im fishing, water clarity etc. Pick a line that fills YOUR needs and set your drag accordinly! (Im not a spelling bee!) :wink: