I have an Amby and love it! I used it from a couple weeks on and did not have any problems with dd sleeping. Not sure if the Amby contributed (she does love any sort of motion, loves it loves it loves it!!!) but it just seemd to be such a comforting, comfortable sleeping arrangement. I liked that it rocked when she moved and was not a flat surface, it was also easy to travel with and set next to our bed nicely. She had no problems transitioning from it to our bed and vise versa during times that she slept with us. She is 7 mo now and has grown out of it,
(she is a big girl, 24lbs)
I can't imagine not using it for our next child!
I have not heard of the other! I will have to check it out!

I can't imagine not using it for our next child!

I have not heard of the other! I will have to check it out!