One glaring difference between the two (outside of talent) is Kaepernick is a punk.

I haven't followed the guy much off the field but why is he a punk? I haven't seen anything to led me to that.
Once again I don't follow the guy much

You don't have to follow him only have to watch his last game to see it. For example, didn't slide, took a good hit because of it in the red zone, got up and spiked the ball at the defensive players who hit him (like a punk), 15 yard unsportman penalty.
I'm kinda old school though, I like the players who let their play speak for them. When I say he is a punk, he is one of a huge bunch of young players just like that. He undeniably has great talent and a HUGE arm. He is the starting QB and therefore leader of the team, act like it or go play for the Panthers.

I gotta' agree with this sentiment. Let your play do the talking. The one thing I liked best about Barry Sanders was he would just flip the ball to the ref after every touchdown. No dance, no 'in-your-face', he knew how to act like he'd scored before.

When Kaepernick became the starting QB, they started with all the human interest stuff about all the adversity he's faced to become an NFL QB and blah, blah, blah, blah ... and I thought 'rubbish', let's see how the kid handles a little success before we put him on a pedestal.

Looks like he might have a chip on his shoulder, eh?

Loved Barry. Did you watch NFL Network's "A Football Life" on Sanders? A great watch.

One of my all time favorite non-saints. I don't agree with his reasoning for quitting, but I do understand.

I loved watching him play, and I rarely love watching anyone play who doesn't wear Black & Gold.

Marino and Sanders are the only two non-saints that I pulled for as hard as I pull for Saints players. Can't think of anyone else in that company. Even Earl Campbell, Warren Moon, Cornelius Bennent, and Derrick Thomas are a notch below.