I had one from birth and it has pluses and minuses.
The pluses are it can be kept near to the bed which is lovely, it swings gently which is lovely for the baby. It does seem to help sleep, my son slept a minimum of nine hours a night from ten weeks old and went from 6am to 6pm not long after that. He may just been a good sleeper though. He really did seem to enjoy it and I have some lovely pictures of him in there.
The minuses are it can be hard to get your baby in when they are already asleep without waking them. So you can end up getting them to sleep somewhere else and have a nightmare trying to get them to bed that way. Also a baby will learn to bounce themselves in it which is cute, unless they are like my son and bounce it so forcefully it rips the material
. He found himself really funny bouncing it as hard as possible. We ended up moving on from the Amby bed when he was quite young because of that but I am not sure how long it would have lasted otherwise as he is a taller child and I don't think he would have stayed in it much longer.
With regard to colic, I'm not sure he had colic badly which was only helped by comfort milk however he also slept through the night. It may have been in a more traditional cot the colic would have stopped him sleeping.
I would defiantly recommend getting more than one mattress (and having a cover on it) my son wet through his so many times which he never seemed to do in the Moses basket, it must have been the position he was in.
The bottom line is I did enjoy having it, it was a talking point among the health visitors and midwives. Each one of them had a play with it and made comments about it (positive and negative), not one of them had seen one before which surprised me.