I have the classic mono and use mine every day. I love it and except for some wear on the corners the canvas has held us really well and its almost 10 years old!
Canvas for sure! I have both mono and DE and love them!
Canvas, definitely. They are extremely durable and aside from eventual fading of the gold coating on the zipper pull you'll see very little wear.
I'm quite clumsy and drop my keys often and for that I need canvas!!!!