Infernape vs Scrafty
Infernape is more a physical sweeper, used to sweep teams with strong STABs such as Close Combat, Flare Blitz and a priority Mach Punch.
Infernape has the ability Iron Fist that power up all punch moves, great ability for him with a STAB Mach Punch for revenge kill.
Scrafty is used to Wall and resist some pokémons. It has decent Defence and Special Defense, knowing Rest and having great abilities to decrease attack such as Intimidate or to increase attack such as Moxie. Shed Skin is a great ability to but I don't like it, you can use it to prevent status-problems. Dragon Dance or Bulk Up are needed for is set. Has great moves such as Head Smash (recoil hurts), Drain Punch, Hi Jump Kick, Crunch.
Both are physicals while Infernape is weak to water, ground, flying and psychic and Scrafty weak to fight, flying and fairy.
In your team, Infernape's weakness are covered by Greninja/Blastoise, Rhyperior, Aegislash.
Scrafty's weakness are covered by Aegislash and Rhyperior.
The movesets
Infernape is a perfect set. Jolly and Life Orb great combo with Iron Fist and some punch moves.
Scrafty if you want it to be a physical dragon-dance sweeper, go with Life Orb and had Drain Punch over Hi-Jump-Kick, if you want to remain your set, Life Orb is a great item for use.
If you want it to resist some attacks, then use Intimidate ability + Dragon Dance with Drain Punch and Rest, having 252 Sp.Def / 128 Def / 128 HP. You can add Toxic for beeing more annoying.
Conclusion
If you want a special sweeper, go with Infernape. As alot of speed and attack.
Like I said, Scrafty hasn't the best Attack but has great Defense and Sp.Defense.
Hope this helps.
