Well I saw the paediatrician today & he wasn't concerned about the head shape.
He thinks it was a 'side effect' of Oliver having one neck muscle shorter than the other when he was born (he had a real preference to looking over his right shoulder), which in turn made him favour his right side for sleeping and hence flattening off on that side.
Now Oliver has better movement of his head & looks around more - not always to the right. The Dr thinks this will sort itself out over the next 6 months, but had also booked us an appointment with a pysiotherapist to go through some passive physio to help Oliver out a bit.
I asked about the helmet, but he said he'd worked with the child cranial specialist & he didn't recommend the helmets as treatment.
I asked if come 6 months down the track its not better, is there still time to do something more physicl about it & he said yes, up to 2-3yrs the bones would still be soft enough to change the shape....
So - I dunno what to do now. Do I wait til he's a year old & hope this physio sorts it or do I go get a 2nd opinion from the helmet people?