I think that as I see it (the reticle in relation to the target) with my 6-24x50mm PST FFP MOA scope the reticle is the same thickness at 6x as 24x. By this I mean that at 100 yds. at 6x the reticle can be held inside a .22 cal. hole in your target ( if you could see the bullet hole). When you turn the power up to 24x the reticle "looks" thicker, but your target is larger in relation to the reticle. Even though the reticle "looks" thicker at 24x it will still hold inside a .22 cal. hole in the same target because the hole is 24 times larger.
I think that a FFP is more useful for long range then a SFP. A SFP reticle stays the same thickness at all magnifications. When aiming a SFP at longer ranges the target gets smaller while the reticle stays the same thickness which can cover up your target like a prairie dog. In order to make the prairie dog not be covered up with a SFP you would need to increase the magnification to make the dog larger. With a FFP the reticle always stays the same thickness in relationship to the target at all magnifications.
When I hunt deer here in Georgia almost all my shots are from 10 yds. to a max of 200 yds. In this situation I like to use a SFP scope.
If anyone disagrees please chime in. This is a good discussion and we all can learn from our experiences. Even me!! If I am stating something that is inaccurate tell me about it.
"Aim small miss small",