Active duty Marine here.
A lot of things said so far in this thread, I won't try to respond to them all, but I just wanted to point out something about the training which should resonate with anyone who has done R200 in the Stumps.
As someone mentioned, the majority of the trigger pullers are 18-22 year old kids, which means that when clearing a house and taking fire from upstairs, it's going to be a 19 year old who has to lead the charge upstairs, and he HAS get up the stairs - can't stop, can't hesitate, can't give up ground, or all the ground you did gain will be for nothing.
So why does that LCpl run up the stairs without hesitating? Because he knows his buddies are right behind him, and they're not hesitating either. He can trust them because they have been in a ton of shitty situations together, from boot camp to MOS school to FEXs to midnight patrols in the freezing rain.
So when the training ridiculous or inane, just know that it does have a purpose. I hated drill, but after doing it for weeks and weeks you realize how many commands you have an automatic response and muscle memory to, and those will transfer over to operations, so that you have an automatic response and muscle memory for brevity codes and IA drills.
Good luck with whatever you decide.