Welcome to the forum Stevie!
Its a bit difficult choice as they are both good bikes. I would think it comes down to character and horsepower. If you like 4 cilinders and lots of power the F4 is the one. If you have a weak spot for 3 cilinders and don't need that much power it is the F3. Personally I would always choose the F4 as I am afraid that I would miss the excessive power with the F3... And I am a real 4 cilinder adept.
Its a bit difficult choice as they are both good bikes. I would think it comes down to character and horsepower. If you like 4 cilinders and lots of power the F4 is the one. If you have a weak spot for 3 cilinders and don't need that much power it is the F3. Personally I would always choose the F4 as I am afraid that I would miss the excessive power with the F3... And I am a real 4 cilinder adept.