Oh Crap, here we go again but I will get my vote in first.
Since this IS Long Range Hunting forum! I like second focal plane scopes. The reason is the reticle I have choosen stays small as you crank up the power and the target increases in size. This allows a more precise point of aim on any target. This is most useful at distances beyond 700 yards where a laser rangefinder is more accurate than ranging with a reticle by far. However if you feel you do not wish to use a laser RF and do intend to range with your reticle then a First focal plane scope could be desirable to you. This is because the reticles will remain calibrated to what ever method of measure ( moa or mils) at any power that is selected. The SFP reticles are only calibrated on one given power for ranging. So really, it depends on what your field practices are for ranging, reticle, or laser.
When you are looking to see what the scope is you will need to look at the spec sheet.