It is what it is. FF will improve your speed some vs B-50. I like the extra speed and the feel of FF that's why I use it.
If you like the way B-50 feels, and don't care about a few fps then keep using it.
The last bow I made came in at 38 lbs after final sanding and shoots 158 fps w/ about a 500 grain arrow. It blows by my 45 lb, 47 lb, and 51 lb bows with the same arrow, and it draws smoother. So it basically obsoletes those 3 bows. It's a lot easier to shoot all day and it shoots flatter.
Design and construction makes the biggest difference.