Okay, so I'm actually putting mega Lucario in my online/competitive team.
However, I can't decide either on physical or special. I get physical is amazing but my only grip with it is - simply put - status condition.
Poison Barb's, static, flame body, etc.
Special has no physical contact and I find that a huge advantage for any Pokemon that is a glass Cannon.
I only see a 5 point difference in base stats and that's minimum in the grand scheme of things
That's all being said, here is my build for mega special lucario:
Lucario @ Lucarionite
Ability: Inner Focus ---> Adaptability
EVs: 252 SpAtk / 4 HP / 252 Speed
-Calm Mind/Nasty Plot
I haven't even touched IV's yet either...
Any advice would be greatly appreciated.