although i'm surprised GW hasn't chimed in on the safety of using the cps since it is copper. i'm switching to SS tubing modified kinda like a wort chiller and then using the same fittings that the dip tube is tightened with to get me to 1/4" hose fittings
It is actually the sulfur compounds in butane that are of concern with the copper, not the butane. I haven't seen any evidence of corrosion with the low sulfur butane that we use.