I lived there for 18 years until around 3 years ago.
It's horrible, I would never go back, even though all my immediate family are there. There are alot of problems there under the surface, has a big mental hospital there, as well as a public one. Walk down the main street and you'll see where they are discharged.
Yep, stay away from Harlaxton, Rockville and Wilsonton. Out near the army barracks is nice at Carbarlah, I lived around the corner from it, but you have to go into town for anything (although they have a shopping centre in Highfieds).
Wrasse also summed it up nicely.
It's got a depressing feel over it, maybe I was there for too long. I would never choose to live there, that's for sure. Water is at crisis level and they rarely get rain. They had a referendum on recycled water recently, most voted NO.
I personally would choose anywhere over Toowoomba to live. It didn't used to be too bad, but lots of bogans just seemd to move there and many people with mental problems and then the drought and it went really downhill.