Well we ended up buying the Amby one that we hired from Hire for Baby as she was wanting to upgrade anyway!!! Thanks for all the advice ...I am still a little concerned but think I will move him out once he is anywhere near rolling, and we are always sure to put him on his back and not his side in it. It had made such a big difference in his sleeping - he will go for 4-6 hours every night after his 7pm feed which is just wonderful and he clearly isn't struggling with pain in it.