I had a Banks on my 01 with the NV5600 for over 100k miles with no problems, and my experience with Banks tech support has always top notch. My dislike on the 01 was that it cut out abruptly with the cruise control, and did not work below 30 mph.
I've got the jake on my current truck, but it doesn't seem to have quite the stopping power of the Banks in the 01. It's still acceptable and effective (less failed vacuum pump after 40k miles), and has a much smoother interface with the cruise control, as well as staying engaged until the vehicle nearly stops.
I was told that a missing hose clamp on the vacuum port tube on the vacuum pump may have possibly allowed a vacuum leak and caused early pump failure. From all the other posts I've heard about this problem, I am not holding my breath that this pump will last any longer, time will tell.