There is one thing your forgot, there are no definite statements when it comes to drag racing. There are simply too many variables to make any form of a definite statement of what car is faster, or what can will never be beat. I have been drag racing and street racing for 30 years and my family experience goes back over 50 years, so I can definitely tell you that there is never a definite outcome to any race. Here are a few examples that come to mind.
I was at the street drags back about '99 or so at the Rialto Airport Drags (1/8th Mile), my race car was broke so I was racing my daily driver '88 Camaro that had a 190 HP TBI 305, not fast in any way possible, but racing anything is better then watching. A '97 or '98 Camaro Z-28 was lined up against me, for the day those things were fast with 275 HP and a 6-speed trans. That Z-28 was much faster then my old '88, period, end of story. But guess what, the driver couldn't get his launch down and was seriously blowing the light, so I beat him on that first race, he was pulling really hard at the top end and he would have won if the track was 30 feet longer, but I still got him at the stripe. We hot lapped and squared up again and I beat him again. This happened 4 or 5 times before he gave up. That poor '88 Camaro could never win a race against that Z-28, but it did, several times.
My race car was a Super Comp Dragster that I also ran in Super E and Quick 16, I owned the track record for both speed and ET at Rialto. At the time my dragster was running a 632 on alki and turning 1100 HP and 1300 LBFT while only weighing 1700 LBS. A buddy of mine decided he wanted to set the record so high that no one could touch it and he had just the car to do it, it was a Nostalgia Funny Car that was running a 500ci Hemi on Nitro with over 3000 HP. His average 1/4 mile times were in the 6.0's while my fastest all time was a measly 7.0. He was much faster then me, he had much more power then me, so there was no way that I could have kept my record, right? Wrong! He could never get traction and the record stayed in my name till the FAA threw a fit and closed down the track.
Back in the late 80's I built a awesome '76 Camaro for open road racing, this thing was running a 6" rod 383 and would turn 8000 RPM, it isn't much now but back at that time 550HP for a daily driven street car was unheard of. Unlike all of my other builds that I used manual valve body automatics, this time I used a wide ratio M-21 4-speed, that went into a 2.73 rear gear. This thing was aerodynamically limited to 180 MPH, there were only a couple cars made in the world at the time that were faster, like the F-40 and Countach. I was driving it about a week, still unfamiliar with not only the car but also in using the trans, when a guy pulled up next to me in a mild built '66 Mustang. I not only knew the driver but I also helped build the engine in his car. It was just a mild 351 Windsor that was maybe pulling 300 HP through a C6 trans and 3.56 gears. Our cars weighed the same and I had 250 HP on him, it would be fun to show him what REAL power looked like. We were doing 35 when we both hit the gas, his car zoomed ahead, my car went no place, I never shifted out of 3rd gear. I later figured out that this Camaro would run 60MPH in first and shift into 3rd at 120, but in 3rd at 35 MPH the engine that came on the cam at 5000 RPM was idling at about 900 RPM. It would have been a easy win if the driver had his head in the game, but I didn't and I received years of teasing because of it.
So Motortrend and Car & Driver say that a Mustang 5.0 is much faster then a Genesis R-Spec, but I live in the real world and know that there is no definite outcome to any race.