I have 4 of them too. Mine are red and blue. I love mine. they stack great, take up less space. Easy to clean and are sturdy. I do have the padding that goes in the chair (I only have 1) but its for my little kids that come at a younger age, otherwise I don't use it at all.
Now I do find the trays are a bit hard to take off and the trays don't slide for snug fit (if thats what your looking for) but other than that they are great and really do recommend them. Mine are stacked in a corner.