Shock: Would not touch Jetstar having had friends expereince cancelled flights, late flights, booking system muck ups etc.

and yet you would use Qantas, that doesn't make sense.

Qantas and Jetstar are two different airlines, same owner but serving two different markets - Jetstar being the budget lower service one.
Much same way as when Air NZ had Freedom Air as a separate budget airline and which they dumped 3 years ago as they could not make it fly business wise and so rolled budget into Air NZ.