If you ask, many people will tell you that Medellin is nicer than Bogota. It is warmer, more organized, and cleaner. I liked it. To get a good view, I’d recommend taking the cable cars over the city. 
Much of Medellin was built by Pablo Escobar. There are tours relating to his life and death. But there is much else to see in Medellin. And, the food was pretty good. I had a halfway decent Pad See Ew at a Thai restaurant near the Hotel Charlee (which also has decent Asian fusion food at its rooftop poolside bar).
I’d recommend visiting.