"Warning!! You must replace ALL brake lines at once."
Hmmm. So, I would read this to mean "Warning!! Putting little tubes through the brake line changes how quickly the brake fluid flows through the line!!!" And unlike their claim that the cooler brake fluid will flow faster, I'd be inclined to think that all those obstructions to the flow would increase the time it takes the fluid to flow through the line.
I would also be concerned that you now have "pre-drilled" holes in your brake lines, with that much more additional surface area to fail. Not to mention those little tubes can't be adding to the overall burst pressure of the line. I obviously don't have them in hand, but I'd be concerned that the construction would be more likely to fail at the intersection of all those little tubes. Sometimes more complicated isn't better, and with brake lines I think I'd be inclined to stick with the "Keep It Simple Stupid" theory.
