Greyhound Nail Trimming

I get really scared trimming Dermit's nails with a conventional clippers. I have heard of devices like the Peticure or Pedipaws nail sanders. Has anyone tried these? If so, how do they work? or Does anyone have any sage advice on how to trim nails without hitting the quick. Dermit's nails are kinda dark so it's tough to see how short I should go. Any advice would be much appreciated.