Royal Purple is the only thing we use in all our cars. I use the 5W-20 in my '07 twin turbo Mustang and my daily driver Escort. Dad uses 10W30 RP in his '07 F150, his wife's F150, his '84 Thunderbird with a 512" big block (9.21 at 146 mph) and even the lawnmowers around here. Best stuff on the planet.
+1 I have used 5W-20 RP in my supercharged 06 GT convertible for about 10k miles. I will be putting the same oil in the Shelby GT at the first oil change! I believe it was Horsepower TV that showed a 10rwhp increase on the dyno by just changing the fluids to RP.