Well, again, it's tough to generalize "the best" helmet, because there are variations from the ESB to the ROTJ. The ESB and ROTJ are not as different as was once thought. But, there are differences significant enough for me that a helmet made to be ESB can't be passable as an ROTJ and vice-versa. The "movie-sized helmet" is the best, current interpretation of the ESB helmet. Sarge's helmet, on the other hand, works better as an ROTJ helmet.
A couple of quick notes: The Aurora helmets are the movie sized helmets which are ESB helmets. The mystery helmet was rumored to have been molded off of one of the screen used helmets, although the shape resembles the RotJ more than the ESB. So if its origin is true, it is more likely that it was pulled off of the RotJ helmet.
Someone please, clarify about the "Aurora" and the "Sarge's" versions. I mean, give me links to the pics to see for myself what it is all about. I've seen the new Jango helmet at Party City and it looks really big and accurate. As of me...the best looking one is (or will be)....MINE once I start customizing it and paint it. (I have the '95 DP version). Seriously guys, let me know and send a link or pics to me.