FFP & SFP scopes both have advantages and disadvantages you have to find what works for you. I like SFP rifle scopes as I prefer to start around 3X power on my variables for the low end. With a FFP scope the reticle can be hard to see since the reticle size increases as power increases. The SFP reticle stays the same across all power ranges and as long as your top end power isn't too high, then the reticle never covers up too much target.
I think.when you get into scopes that have a starting power of 6-8X and a top end over 24X then FFP reticles are a better option. Plus on MIL or MOA ranging style reticles you are able to range estimate at any power setting. Whereas the SFP scope you set on the highest power to range.