I've used FWH a few times but since I use a 90 minute boil, it's a little harder to figure out actual IBU contribution. Since I get most of my IBUs later in the boil, I mostly don't worry about FWH and just do a reasonable 60 minute addition. I can't say that it made a better beer but I'm sure it didn't hurt it. Some brewers swear by it but I can take it or leave it.