I am running to finally buy a baitrunner real on my lunch break (payday). I am going to pick up the Shimano 4500. I need help quickly knowing if braided lines work well on this reel. I intend to put 20 # Fireline on it as I have had no issues with it on Penn 6500's, but they are entirely different beasts. Any advice ASAP would be hugely appreciated.

Shouldn't be a problem - fireline is the way to go.

If you're not at lunch yet, I have 60 lb Whiplash on my 3500 for the first time this year, and it's awesome......:)