The mechanic can't see anything about the car that would be causing the tyre scalloping. Shock absorbers and wheel bearings are fine. Other suspension bits need work eventually but they're not the cause. The mechanic says the tyres are going hard with fine cracks starting to show and that is the cause of the scalloping because the tyres are not getting sufficient traction on the road. Low kms could be an issue - 44000 in just under 4.5 years or less than 10000 kms per year.

So the next step is deciding which tyres to buy that will suit a mix of urban, highway and unsealed road use but not technical 4wding or beach driving. From the reviews I've read so far that's anyone's guess. Everyone has their favourites but not everyone has the same favourite.

Anyway, thanks for all the advice and comments. It's always good to hear from people who know a lot more about cars than I do. ]

Cheers