You are suggesting failures of properly sweated connections with what kind of pressures? Of course, when you sweat a joint, you likely will anneal the area, so safe working pressures should be below 300 PSI or so.Mine is all soft copper with flare fittings and Leak Lock, a refrigeration sealant used to make leak free joints. Soft solder will creep and blow apart too easily. Keep an eye on them. Where I worked went with silver solder after several incidents with regular water pipe soft solder.
Charley
Unless you have a very high pressure system IMO copper pipe is total overkill, not to mention very expensive, the same with black iron pipe.
I used the Rapid Air system and full disclosure, before that I used [GASP] Sch40 PVC. Yeah, yeah I know. It lasted almost 20 years.
I just became aware the 1/2" RapidAir tubing I used is only good for 5 years.
We'll see.......
So Dee2, if I had to do over, I'd go with RapidAir MAXline in the 3/4" size b/c it is has a longer lifespan.