Just adding to this thread as I had the Polestar optimisation software installed on my 2012 XC70 by my local Volvo dealer. It cost me £675, inc VAT which I can recover, so for £562 I have the uprated software and I am very pleased with it. I'll not say that it is the best value for money but since there is little choice if you want the genuine Volvo software which cannot be overwritten when software updates are made I will only make judgements about what it does rather than what it costs.
The performance is definitely improved. My car is an auto and the acceleration in "D" is now sufficiently good to eliminate the need to drop into "S" mode for rapid take-off or overtaking. If I do use "S" mode, it accelerates quicker than I am likely to need it to. I'm sure that there are track style ECU rewrites that lay down a lot more power but I'm satisfied that this Polestar upgrade give me more than enough extra power for road use, stays in the ECU after software upgrades and is recognised by my insurers as a Volvo specification. In reality my "Grandad Wagon" can now take on BMWs, Audis and the like and give them a real surprise!
