I had a Sora FD break on a 2002 Specialized Allez, and replaced it with an Ultegra. I had a 105 FD break on my 2007 Roubaix and replaced it with an Ultegra. Both were triples. Both worked fine with the Ultegras, but I can't say it was a big, or any, improvement. They just both work better than the broken ones. If it breaks, replace it. If not, why mess with it?