The Stakos cannot be used legally on the US territory. That's why everytime we want to us ours we have to perform a complicated procedure which involves your very own fellow countryman putting up the flag of the United Kingdom and announcing that the ground in a 5 feet radius around the flag is now in the domain of the Queen Elisabeth the 2nd and everything in it is subject to laws set up by her majesty, especially the bulk tank and the filling station. After that he fills the Stako and than transfers it to a US citizen standing outside of the Uk territory - it involes a lot of customs paperwork and was a bitch to do in the beginning because everytime we did that, a HMS Customs officer had to be present and we had to get special permits to be able to transfer the bottle with the air inside.
Please tell me you made all that **** up?
They are currently NOT LEGAL in the States. That may change, but I highly doubt it will change before HB.
As for transportation issues, I've brought mine back and forth from the states for the last year or so with no issues. I think that 'officially' the NPPL would have to refuse to fill your tanks, although I have heard of Pro's using them in the States.
If your dead set and having the lightest set-up posisble for the week, you could always pick up an DOT approved Inocom tank over there (I THINK they're the lightest DOT approved ones out at the mo). Would probably be a lot less hassle than all that stuff that Fizs did.