I would rate it 8/10 as far as pure punching power goes. Not an explosive puncher like his brother Rafael but his punching technique, timing, and accuracy is what makes him such a great and deadly hitter, along with his incredible combinations. He's one of the best punchers in the modern era.
He's not called Dinamita for no reason. He's a bigger hitter than Pacquiao at any weight class. Especially after he started doping. 8/10 pre roids. 11/10 w/ roids.
I dont know. I rate Pacquiaos power at 122 to be ATG. Marquez was definitely the harder puncher at higher weights though.
I would say that Pacquiao was the faster, more explosive puncher while JMM is the better puncher, technique and accuracy wise. That makes both of them even in terms of punching power IMO.
It's good, but not ATG IMO. His punches have a more devastating effect since he puts them together so well, and walks people onto them. I'd say it's a 7/10, but can potentially be as damaging as a 9/10.
Power is sperb but not ATG status, it's his technique, timing and counterpunching ability that helped him rack up those TKOs.