have you looked into the price of inconel or titanium recently.. and yes in the case of using those materials obviously no expense spared purging isnt goin to make f**k all diff to the price
for someone like me who does this work from home as a hobby to help mates out the extra expense isnt worth it to me.. its not the gas that gets me its another bottle rental, reg, fittings and wat not to go over the end of the pipes in all different sizes as i work with anything from 3/4inch up to 4inch .. perhaps you could show me a few pictures of the setup you use