Flat head: has anyone tried the sleepcurve mattress? Does it work?

[naturopath]

Is the sleepcurve mattress good/safe/worth buying?

I have been using it for my son since birth and if you look at the photos in my profile you'll see he doesn't have any flat spots, although he still has a patch where he has rubbed the hair off. He also had his first cold a couple of weeks ago and didn't seem too bothered by reduced airways which the mattress is also meant to optimise.

It comes with a zip-off washable mattress cover and I bought 3 fitted sheets, I think they were BTGOF at the time, and they wash and tumble-dry well without shrinking.

I have already bought the next one for when he moves into his cotbed.