I guess I'm the only one who has absolutely no problem with the Blackmarket thing?
Press down on the d-pad. Then press Y while looking at the ground. Easy.
Oh, and press 'A' as soon as you hear the guy start talking, since you can just skip over those 'Hey amigo! what do you need?' cut-scenes.
I will agree that the lack of buying more then one item is a tad annoying, but if you collect what you just bought and use the black market beacon again, the little black market cut-scene is skipped over, and you jump right back into the menu. So that's not so bad.
And I can't help but think there was some serious exaggeration with the length of a death. I just played this a ton this morning, dying a bunch on those stupid plane challenges that make you fly up and around bridges, and the death sequences never seemed long to me.
Over all, the game is just about having fun. Story and voice acting take a back seat, but they are so very bad it's funny, so that makes it better. It's about jumping around, blowing everything up. And it's a blast (No pun intended). It's certainly eating up my time! And it's always fun to experiment with the grappling hook. Like when I grapple a motorcycle that's chasing me to the ground. FLIP! Awesome.