I just had the front and rear bars and noticed an immediate effect, which I think I understand and can explain. As y'all know, when you do aftermarket motor mounts you get increased NVH. The amount depends on the design, as I have tried a couple of different ones. Well, when I started my Speed I noticed a decrease in NVH at idle. When putting it under load, the stability increase was notable, just a perception on my part of "stiffness" in the stability sort of way. I am very pleasantly pleased with the addition of these bars. Thanks for making an excellent product, well made and made in the USA! Blessings in Christ Jesus!