Blaziken has a amazing ability, speed boost. That makes Balziken faster in every turn. And it's become hard to revenge kill it.
It also has a offensive typing, fire and fighting
It has access to Sword dance, that can raise it's attack. Blaziken can also learn Baton Pass, that pass it's all star changes. Blaziken has 120 and 110 base Attack and Sp.Attack. It has Brave bird, Flare blitz, Bulk up,Blaze kick and Stone Edge.
While Manecteic has a good Sp.Attack and Speed and some good special move like Overheat, Volt Switch, But I would prefer to use Mega Blaziken.
However, Mega Blaziken isn't much bulky, so you may get killed by priority attacker.