Its the only one which I can see actually working ingame currently, you know what valve is like, they don't like making weapon stats so the machine gun backpack would be hard to do, the teleporter one, fuck I have no idea.
So it's either that or it'll become a cosmetic item, I'd personally prefer the lesser if it does go in.
I talked with Brandon about the reskin items when it was only limited to the Postal Pummeler and the Nessie's Nine Iron (he was still with the TF team at the time, now he spends his time working on DOTA). He said that it was an experiment to see how the community responds to them; and that implies that they were also going to monitor the sales figures of them. NeoDement's Bootlegger and Scottish Handshake are a continuation of that experiment, as are the Wanga Prick and Unarmed Combat by GG_Underscore.
There's obviously a point where people would get sick of reskinned weapons, I think we've pretty much come to that point; let's see if they act accordingly.