My .02 (and FWIW)--Fluoro carbon (from my experience) has been a waste of money (and time) for salt water applications. Money---it costs more then regular mono (which is tried and true) and I'm not so sure the extra expense is warranted because salmon just ain't leader shy in the salt chuck.
Waste of time? Again, in my experience, in order to use Flouro carbon properly, you'd better know how to tie a double uni-knot (which is very time consuming) and know how to tie it often and fast ( or get comfortable breaking off fish because Fluoro is very unforgiving when it comes to knots).
Lower pound tests of Flouro----I used it up in Alaska last year on "production" steelhead fishing, meaning hooking lots of fish each day under fairly demanding conditions. This gave me a pretty good idea of what tackle will put up with. Short answer summing up my experiences--- 8 or 10 lb Max Chameleon or Ultra Green put up with four times the abuse (beaching fish, pulling snags free, yanking gear out of the bushes etc) then did 12 and 15 lb Seaguar.
Yes, there were times that I thought maybe I hooked fish or had bites on the Seaguar when fishing in high-noon / bright sun / spooked fish conditions that maybe I wouldn't have gotten on the Maxima Chameleon, but I was also amazed at how easy it is to break off fish using knots you would have bet money were sound. All your tried and true knots you've used with mono (improved clinch knot, palomar knot etc) ---they are somehow compromised when using Fluoro.
I'm with FD and Nog on this---leader shy ain't in the same vocabulary as salmon fishing in the salt chuck, but if you think Fluoro is going to somehow give you a confidence-boosting edge, jump right in, but at least stick to the heavier pound tests (40 and up) and then go out and learn the double uni knot!
Here's a primer:
http://www.youtube.com/watch?v=OGZ8SBI8sGI
My guess is, most of us could tie up three straight Monofilament rigs with an improved clinch knot and be in the water fishing by the time a guy tied up one Fluoro rig with the double uni....
Again, just my experience--results will vary...