I fully agree that any injector will need to be rebuilt, or replaced with new eventually.

Understanding where the line is that you draw to replace them is a bit fuzzy!

I was going to replace mine with all new injectors but tried the purge first instead. The improved difference purging made put for me the new injectors on hold!

I really don't think putting new injectors in now could make much difference, maybe I'm wrong but when purging begins to fail to make the huge improved change, I will then buy new injectors.