Ahh quite honestly for the first few years of plumbing supper you have to have an empty head and an open mind.
my boss told me a ton of stuff was best practice and a few years down the line i now know he was being a tit.
as such you cant swear 100% that somthing is right till youve been doing it for a while. As we talked about plastics vs copper
you couldent see the advantages of copper because you havent used it enough!
as i said with more experiance you will be able to better understand the pros and cons of each thing.
try not to defend your ways to the death
because in three years you will most likely think "oh no i did that back then......thats gonna haunt me!"
Three years ago i ran an oil line at my house just copper in a trench.
this summer im digging that up, putting a small duct in, with 28mm speed fit through it with the oil line in that.
why?
because three years experiance has taught me how much of a tit i was for not doing it like that in the first place!