so it's common practice in the uk to expel the gas into the dispenser and, from there, into a balloon?From what I recall it's still not recommended to take gas directly from the dispenser as it is still at very low temperature and can be damaging.
in my experience, the temperature of the gas when it's been expelled into a balloon from a cracker and the temperature of the gas when it's been expelled into a dispenser are pretty much the same so they're broadly equivalent (from a harm-reduction point of view). the important thing being that the immense pressure in the nitrous bulb has been relieved (and the temperature raised).
alasdair