This Roush-tuned Mustang is being touted as the “World’s Fastest Manual-Transmission s550 Mustang.”

This is the 2015 Ford Mustang ROUSH Warrior, and Military Autosource will only sell it to you if you’re U.S. military personnel serving overseas.

Roush Performance’s latest effort aimed at pushing the envelope is a more powerful version of its special-edition “Warrior” Mustang.

With all that power under the hood of the new Stage 3 Mustang, Roush still managed to meet a 50-state EPA certification.

This year’s slate of Roush SEMA show cars includes an 850-horsepower Mustang powered by a supercharged GT 5.0-litre V8 engine featuring a Roush TrakPak,

Following earlier speculation that the horsepower for the new Roush Stage3 Mustang would come in somewhere around 630 horsepower, we’re now learning the official number is actually much higher.

Roush has released photos of its first run of production-ready 2015 RS Mustangs, and from the looks of things, there should be some pretty happy customers waiting in the wings.