For 501st you can have dent or no dent with either pack.
The Mercs are wrong in the way they divided the two kits. The fact is that Jango has the dent on Kamino while he is wearing the classic jet pack. I have stopped offering advice on Jango Fett on the merc boards because there are a number of them that just have dug their heels in and won't accept screen shots to change their minds. I have seen them tell people the thighs are wrong when they are in fact correct........but I digress.
My Jango Fett is approved in both clubs and I have both packs, and both helmets. But I have always trooped with the undented helmet.
As I mentioned above, to be really precise the Geonosis version should only have one pistol as well, but I always troop with both pistols even when I am wearing the stubby pack.