Shimano Bug

I have just read with interest, Grahams review on the Shimano Bug ruck sack, I have just purchased one for myself, I am left wondering though are there two models of this rucksack.
The one I have, has no scuff pads, on the bottom but it does have a built in unhooking mat at the rear. I am not worried but I should be interested to know are there two models of the same rucksack?

I think there are differences in the range, I've got a Bug large Caryall... Great it is, cept when I fill it I cant lift it....

But, I have seen a diferent large holdall with 2 Pockets on the side, not 1 big one....