I have the P3 now, and plan on upgrading to the DirecLink. There's two thing I don't quite like about the P3.... 1) If you turn up Boost so you have good braking at highway speeds, its grabby at slow speeds, and 2) It can be a little unpredictable on snow and ice, sometimes grabbing and causing the trailer brakes to lockup, and sometime not doing anything and I have to use the manual lever to get any sort of braking.
Also, I plan on upgrading to dis brakes with ABS (to also address the above issues), which effectively requires the DirecLink.
