My kids have always had inner spring - just bought a new one for DD3 - so have no experience of latex for kids. Only thing I will say though is that we have a latex mattress on our bed and oh my it generates heat!! I'm usually a pretty cold sleeper - have always had the heaviest doona and an extra blanket with electric blanket through winter - but with the latex mattress I often end up having to throw everything off but the sheet and still sweat, even with the cool top we bought to go on it. Its incredibly comfortable though. Not sure if it would be the same for tiny little bodies but something to bear in mind.