I will try to say both the positive and the negative.
Positive:
1. people can be friendly
2. there are pretty sights
3. it is not as expensive as America
4. the weather can be better than America
5. there are fun things to do
Negatives:
1. depending on where you are, if you do not know Spanish - do not come
2. if you are wanting to work but do not have a Colombian National I.D. Card - do not come
3. if you are wanting to rent a place with no Colombian National I.D. Card - do not come
4. if you are not wanting to marry a Colombian person for the National I.D. Card - do not come
5. if you are tired of getting "double charged" or paying the "foreigner price" of things - do not come