None. It's the increase in torque across the entire power band that makes the difference. Don't forget: Fox GTs were 190 to 210ish HP but packed nearly 300 ft/lbs of torque.
No. You should buy a GT. Maintenance will be easier, it'll hold up longer, and will ultimately have a better resale. If you ever decide to add more power it'll be easier and cheaper with a V8.