it feels like that because its made out of aluminum to cut down weight, but shouldn't affect its endurance.

The fastbrakes and wilwood floating rotor kits have proper fitment with that caliper... i've seen what you mean though, seems like AEM BBKs have a wider rotor surface than pad surface..

THe brembo kit definitely looks hot, especially with cad plated rotors, I don't know much about it tho..