The absolute, hands down, best line around is Power Pro braided line. They carry it at Cabela's, Bass Pro, and are finally carrying it in Atlanta at some Walmarts and Sports Authority.

I've been using it for 4 years and it has NEVER let me down. Power Pro isn't flat like most braided lines, so it won't bite into your spool. You can also untangle the worst birds nest in the world, as well as having fewer tangles. I prefer a Stradic 4000 reel, backed with 15# Ande monofilament. Then I spool on 150 yards of 10# (supposedly 2# diameter) Power Pro. Use a uni-knot splice. Then I tie on about a 3 foot fluorocarbon leader. The actual breaking strength of 10# Power Pro is about 18#, so you can use up to 17# fluorocarbon leader. The Power Pro is expensive, but will easily last you all season.

I use Vanish or one of the other fluorocarbon lines for leader when I'm messing around. For serious fishing I use an actual fluoro leader material. Ande has finally come out with their own fluoro leader, on 50 yard spools instead of 25, and it is less expensive than buying the 25 yard spools. The fluoro leader versus line is stiffer and seems to be more abrasion resistant.

I have used this setup to catch snook up to 20 pounds in South Florida. Stripers and Blue Fish up to 20 pounds on Cape Code. Largemouth, smallmouth, snapper, flounder, sheepshead, redfish, you name it. Caught fluke in 50 feet of water off Martha's vineyard and got to the bottom twice as fast as my brother using monofilament.

Is it worth tying the extra knot? I guarantee, you will get 5 times as many strikes with smart species, and 2-3 times as many with the dumber ones.