I don't use it. I tried it because it was recommended by many, but never found to be benefiting from it. In fact, it only did worse.
FPS limiting within FSX/P3D is also a bad idea since it's not really an FPS limiter in terms of limiting just the rendering part of the sim. The fps limiter is in fact a cycle rate limiter. It combines all of the sim's components into this output. So, if you're limiting it, you're slowing down everything, not just the rendering part. If it was only the rendering part, then it was great. I can also relate to the fps limiter in NI. Unfortunately, I don't use that one either, because it adds tearing artifacts.
As for other software to limit the fps? I have found none that does the job. So all in all, after over a year of experimenting, the best experience is not limiting your frame rates, and with P3D, the blurries issue should be sorted out regardless of your FPS (it's assumed that by not limited your frames in FSX, you're prone to blurries, which is not a certain truth). If after all you're still getting blurries in P3D2, then I'd say it's time to upgrade your rig with a better cpu & gpu (the more physical cores, the better).
Soon though, tearing and v-sync problems will be forgotten. With g-sync and other technologies coming into next gen monitors. This blockage is finally removed.