This one chemical they are adding is quite dangerous, and if you smoke additive free cigarettes like me, you will notice the difference in taste and in the harshness. The "oh its just one more chemical" argument is flawed.
Also, most people have their cherries FALL OUT OF THE CIGARETTE as they smoke it, which is a fire hazard, because the burning material can set stuff on fire quite easily.
Some people are also having lung problems from the new ones, and sore throat problems etc, even though they did not experience them with the non FSC cigs, and still dont experience it with the non FSCs. Some people even break out in rashes from the adhesive.
If you want to avoid FSCs, I suggest rolling your own. You can still use filters with those, and there are even really cheap rolling machines that will do the hard work for you.