Since I drive more than anyone here, especially in DSMs, I feel like I'm pretty qualified to say that running Brad Penn and doing 5-8k km oil changes have presented no issues. I do 5k MAX on the Talon (run much harder) and 6-8k on the Laser since it's all stock. I've put over 20k on the laser alone in the past 4.5 months - 1.5 of which I wasn't even driving it - and it did fine. I've been using Brad Penn in the Talon for a while now and again - no issues on a car that's making a decent bit of power, driven hard, and driven lots. I'm on track to click off 60-80k+ in my DSMs alone for 2015 and it will all be with Brad Penn.

The Malibu doesn't see as much driving but she still sees a fair bit when the weather is nice and Brad Penn has worked well for me there as well.