One thing to keep in mind that with plastic fenders is a stick of just the right size that jams between the tire and fender will accordion the fender up into the fork crown, the front wheel will stop rotating with respect to the bike, and you will find yourself flying over the handlebars in the amount of time it takes for the front wheel to rotate 1/4 turn. You can do the math but take it from me, it happens very very quickly.
So be sure to install the quick release features on the front fender stays. Or mount metal fenders.