Truth be know, I think you just need to be carefull with every insurer. I personally dont think anyone of them is "perfect". I was with Alianz with two cars for over 12 years and never once put a claim in. I notified them I changed wheels on one car from 17" to 19" in standard BMW fittment and offset and they deamed me too much of a risk.
Anyway .... I've allways found Suncorp to be great to deal with but I reciently changed to RACQ as Suncorp premiums jumped up way too much.