30-36 on the stockies should be fine. We own 3 Aurions (One AT-X and Two ZR6's) and they all drive pretty much the same, except mine (AT-X) with a 23mm rear sway bar. All 3 cars have had a harsh life on dirt roads up to 220k kms and the shocks are doing fine. Perhaps you have a faulty shock or faulty bush? Check if any of them have oil/leaky seals/torn rubbers etc. That's a good indicator that they might be dead. The ride quality is about the same as a Magna and older generation Camrys (97-03). I probably wouldnt compare a Commodore to the Aurion as the suspension setup is different. I read that the Omega/Berlina's are the 'comfort rides' and the SV6, SS, SS V, Calais, Calais V are the 'sporty' rides.