Platinum plugs are always a good choice because they will last thousands of years.
Really, they ARE super durable.
I push NGK at the parts house where I work not because they tap into vast pools of hidden HP, but because with their V-cut electrode, they will still get a spark across even if there's a lot of carbon buildup, therefore they maintain your efficiency a lot longer. That's the principle behind Accel plugs (really Nippondensos), Splitfire, AC Rapidfire, et al.
Don't get me wrong, Motorcraft/Autolite are excellent plugs--the best testimony I can give them is that they are HARD to foul out! Very reliable plugs. But NGK's have NEVER let me down in Fords, Chevys, or anything else I've put them in.
Danger Dude can tell you that plugs are a lot like motor oil. Everyone's pushing their brand, but there is precious little actual proof that one is better than the other.
Biggest thing is to go with the plug you feel is good for your ride, and not rely on hype to steer you around. After all, the 'Stang is all about good times!
Tin Kicker :headbang: