I've got a 2009 PCS with exactly the same issue - doesn't seem to be a problem. I've still never yet had a puncture. As NRG says, they need to be well inflated - I try and keep mine at 60 psi.
BTW, the original tubes had Woods valves, which I changed, firstly to Prestas, and now to Schraders. I'd used Prestas for donkey's years and then kept getting a problem with one of the valves on the Kalkhoff, whereby the top part of the valve would come unscrewed a bit, losing all the tyre pressure. I've never had this happen before, but after a couple of flats because of it, I got fed up and switched to Schraders, because I hate not being able to rely on something. Also, Prestas can be a bit sensitive to rough treatment and the valve stems get bent, while Schraders are more sturdy IMHO, and are now available on decent quality lightweight tubes as well as the old agricultural type that tends to go on 'recreational' bikes.
Finally, gradual rationalisation across the fleet means I only need one type of pump connector for bikes and cars - sorted!