For my own Uboat (look for it in the (anti) submarine warfare GB) i used ordinary sowing thread that isn't "fuzzy". Mostly because it was wound up like the antennae wire on such ships would be. Fishing line is smooth though very easily handled... Another thing going for sowing thread is the fact that it will soak up paints and washes where fishing line can only be painted on the outside.
Before i assembled it onto my model i first gave the thread a thin black wash all over to age it and once it was assembled onto the model i gave it a rust wash in a random fashion to conclude with some brownish chalk, again in a random fashion.
Hope this helps you in deciding for your own method
Richard