Our DS was early and spent a fair bit of time in the NIC in a humi crib! He became very comfortable sleeping on his tummy but then they were constantly monitoring with machines so I was OK with that. When he came home it was a nightmare he would only sleep on his tummy on my chest so i spent at least 8 weeks having very little sleep. We bought the Anglecare monitor and my DH insisted that DS would be fine to sleep on his tummy in his own room (in a acot). Emotionally I couldn't deal with this after all the monitor would go off if something went wrong and then what (this was how I felt not saying anyone else feels this way).

We ended up pursuing the sleeping on back ( me more so than DH) and at nearly 6 months now DS still refuses to sleep on his back but loves his side.

It's a really tough one. Tummy sleeping is all my parents knew and I turned out fine. The Do's and Don'ts change so often that i think going with your gut is best. My DS led me and he let me know he was a side sleeper!