I use a variable magnification scope on all long range precision rifles, but shoot mostly at 10 power. The higher power magnifications are almost worthless here in Florida due to mirage. I learned to shoot with a 2FP 10x fixed scope and still shoot them fine.
1st focal plane or second only matters if you are shooting unknown distance.....Most benchrest shooters use 2nd because they don't want the reticle increasing in size and covering the target. Most PRS or tactical shooters use FFP due to not having to move the magnification to rangefind.
I use Mueller scopes on my rentals for our long range precision rifle courses. Can't beat them for the price. They track great and are pretty clear.
http://muelleroptics.com/mt451440