vector is shit don't look for that
try lucienne or Newport
you could've searched the forum for better info since it has already been discussed
about the FasFil the only member I hered of using it was WarMachine
maybe he will chime in on that
either way to test out butane you can simply just spray a can onto a big mirror or piece of glass and to wait till it evaporates to look for residues
if it evaps clean than it should be good, if it leaves residue than it fails