It is well appreciated that people are willing to pay more for properties that are closer to the CBD, have a greater range of services close by (e.g. transport, retail) and offer an attractive lifestyle (e.g. a cosmopolitan community, river views). Given the large variations which exist in these features across suburbs (as well as due to variations in property sizes) there is thus a great disparity in median house prices across the Brisbane metro area (see the map below based on the May 2016 CoreLogic data published in the August issue of Your Investment Property magazine). So New Farm and Teneriffe have median house prices around $1.5 million, while median house prices in many suburbs in Ipswich and Logan are in the $300-400k range. With recent improvements in services and amenities, particularly in Springfield (e.g. shopping centre expansion, rail line, Robelle Domain), and the large projected population growth in the Ipswich region, relatively low property prices could make the western corridor and Ipswich good places for investors to consider.
Source: CoreLogic May 2016 median house price data published in the August issue of Your Investment Property magazine. N.B. data unavailable for some suburbs (coloured white on map).
I have previously discussed the long-term prospects for Ipswich:
Coles backs Ipswich – good investment given strong population growth
N.B. The usual disclaimer applies, that this does not constitute investment advice.
Queensland Economy Watch 
There’s a lot of land out West. The only places for SEQ to significantly increase population over the longer term are either up (higher building density), north of Caboolture or South of Chinderah in NSW. Ipswich is a lot closer than those two other places. Also there are no cross-border issues with Ipswich compared with Tweed Shire. Still, there are many nice beaches along that Tweed coast (such as Kingscliffe) that will become a more enticing place to live as the M1 on the southern stretch of the Gold Coast is improved and the heavy rail line is extended which will cut commute times. At what point will the proximity of Ipswich outweigh those factors? Also, who wouldn’t want that extra hour of sunshine after work?
Very good point, Alistair, regarding the need to consider the Gold Coast and Tweed as competitors to the Western corridor. Thanks for the comment.
Do you know the web site that shows each suburbs median price/rental etc. I had it before but can’t find it. (Heat map ?) you just click on a map/suburb