I'm happy with my Shimano M545's (?) - I'm not entirely sure what number they are.

Essentially, SPD clip both sides with an extra cage around them so I can use them as flats (or with regular shoes) if I want.

I haven't had mud issues, though my tension is set very low.

They've also been good for learning clipless - they don't require me to be clipped in when restarting at a traffic light - I can just pedal and then get clipped as I'm traveling.