I like Deng, but I do have some problems with him. He is a SF, and he has played some guard. He's a very good midrange shooter, but he really sucks from 3 point range. It makes it more difficult to spread the floor, when your SF won't be guarded out at the 3 point line. Its also been rumored that he's looking for 12 mil a year. I don't know that to be a fact, but if it is, I would pass on him.
Now, aside from those things I mentioned, I like the rest of his game. He's a very good passer and has at times, been a decent rebounder for a SF. At around 8 or 9 mil a year, and with his youth being a factor, I would say yes, go after him. But to be honest, I'm not sure that Cisco playing the same amount of minutes wouldn't give you similar stats as Deng, and better 3 point shooting.