I may be simple, but I don't understand the use for a 2nd focal plane scope or even why it exists. On max power, you may be able to use the reticle for estimating distances and what not, but everything changes when you change power and it can get confusing. In a FFP, the distance to your first mil dot is the same whether it's on 20x or 5x... All the guesswork is eliminated, the graph for magnification and holdovers for different wind speeds on different powers is eliminated. If all you do is have a crosshair or simple target dot and you don't hold for wind, then save a couple bucks and get a SFP, but otherwise, in the real world it seems like a FFP is just much better for the application.
I'd get FFP.