My seat post mounted bike trunk acts as a good enough fender for my back tire. I think a front fender would be nice, but I haven't ridden in the rain often enough to motivate me to add one. I know my feet and shins get wetter more quickly from the spray. I even watch the water drops flying off the top of the front tire go up and fly back toward my legs and think, "A front fender may be a good idea."

However, I'm pretty sure my frame does not have any attachment points for fenders anyway. So I just get wet as I did this morning. If it is just a drizzle, the wind generated by riding acts as a blow dryer and keeps things from being too soaked.