I'm going with Kolb. Reason being: The Braves offense this year is decent: just enough to get you some wins.
Now, check out that pitching staff. Sure, behind Smoltz/Huddy, you're scratching your head. Go ahead and check out Hampton and Thomson's second half splits. Hampton will finally put it all together this year, his third lucky year away from Coors/with Leo.
Kolb's K rate might be down, but that's a good thing. He's been talked to about it, and he's said that he's not wasting time, throwing strikes, making hitters pound it into the ground. When his K rate is down, that's a good thing, because it means that hitters are chasing his sinker, and slamming it into the ground.
The lack of XBH's last year was pretty amazing. Kolb doesn't have the fatigue that Smoltz does, I think he'll have to be helped out, but we have a very decent bullpen this year, and a couple rookies will help out with that. (Watch out for Roman Colon)
Horacio Ramirez is a big question mark, because, even with his ERA last year, all his other numbers were bad, suggesting that he was getting lucky, leaving runners stranded. But, I was talking it over with someone, and we came up with that Horacio's SLG against was just .376. Meaning, his pitching style is to not give into the hitter, not to serve up fat pitches, but rather, make the hitter work for their pitch, and that's how he was successful. He gave up walks because he didn't give in to the hitter, but, he has impeccable control, and Bobby and Leo say that it can be even better if he takes a little off his fastball. I see good things in his future..
That great pitching staff, somewhat weak lineup (I actually think Mondesi will have a decent year... you should see some of his Spring Training quotes, can't question his enthusiasm), Kolb is going to get a ton of Save opps. 50 wouldn't be out of the question IMO.