I don't off hand remember the profiles of the Explorer Cam, but I'm guessing if it's ground more for low end torque in order to move around a 4,500lb SUV like I imagine it is, you probably won't like it for a 3,000lb Mustang. Off idle torque and throttle response will be excellent, but it will likely start falling on its face fairly early in the power band, which isn't exactly what you want and hardly justify the better breathing top end you’re installing on the engine. A hard pull down low combined with a smooth steady pull all the way to redline is what most people consider ideal for a street car.
As far as aftermarket cams go, I've never been a fan of the Alphabet Cams sold through Ford or Crane personally. I'd look into one of the popular dual pattern grinds from CompCams or a custom unit from a company like Anderson Motorsports if it were my money. You’ll spend a little more initially for them, but their broad power production and excellent promotion of economy and drivability will be worth it in the long run.
The stock HO cam is unjustly criticized IMO. I ran my full weight '87 LX into the mid-13's on worn street tires with little more than stock ported heads with aftermarket valve springs and Crane 1.7 roller rockers, ported lower intake, under drive pulleys, full exhaust and a custom CAI...all backed with a conservative set of 3.55's out back. And I averaged 26mpg and had perfect drivability all the time.