The best, the fastest, and the most reliable.
 

I'm looking for the easiest, most multi-bike friendly, as well as the most protective clip-on front and rear bike fenders. I have more "permanent" fenders on my snow bike, but for the crummier months, I need something that can be swapped from road bike to commuting bike in less than 5 minutes...maybe even faster.

I'm sure they all present compromises. You may have to make your own to be satisfied.

The only thing that I've had that will swap that fast is the SKS motocross style fenders designed for mtn bikes.