What chews are recommended for nail biting?

Almost all of our chews come in 3 color-coded toughness levels.  

Usually the softest/standard level is the best substitute for nail biting.  

Nails are very thin / easy to bite through, so even the softest level is much more durable than fingernails.  

As far as which design to choose from, the Chew Tags and Arrowhead are the thinnest shape (so the closest in terms of shape to fingernails).  The Chewth Pick is fairly thin as well.