Marking the cut line on the top of the plank first with a utility knife helps a ton. It scores the surface so your saw or snips have a cleaner path to follow. That little extra step made the difference for me last time I installed some.
Oh sure, because what every DIY project needs is another step we all pretend to remember. I've got a drawer full of barely sharp utility knives just for this purpose. It does give you cleaner lines though, I'll admit that.