I also use flurocarbon when fishing spring creeks and while chironamid fishing. This February, I'll be making my annual spring creek fishing trip and 4x fluro or 6x mono is all you can use on trout up to 10lbs in a small creek. In years past, I have seen them scatter at the sight of 5x fluro or 5x mono.
Flurocarbon also is a lot more abrasion resistant and UV resistant than mono...but as mentioned before, you have to use good quality ones. One other thing to remember, since flurocarbon is a lot harder material than mono, when you splice a flurocarbon tippet to a monofilament leader, be sure to use mono that is at least .01" thicker or more than the fluro. Otherwise, when tension is applied to the knot, the fluro will just slice through your mono leader. And flurocarbon stays in the environment pretty much forever...so please clean up after yourselves when you use fluro and bring your garbage home.