I've been reading some scans by a group called Helzone, headed by 'musketgiggity', and I am continually impressed by both their sincerity in their work and their sense of humor about stuff. Basically, if I see Helzone on a scan, I know it's going to be well-done.
Here's an example of why I appreciate them.
(NOTE: This is Korean, so read left to right.)
From the note, I gather that the original reference was to something in Japanese mythology, and rather than leave the name intact and attempt to give the readers a quick synopsis of the history of the reference, they made an idiomatic translation decision and presented something of identical meaning and greater familiarity.
I didn't even notice the translator note at first because the substitution was so well-done that I didn't break thought when I was reading the dialogue. It was only until I moved my eyes to the next panel that I saw it, and realised there had been a footnote placed in the text bubble.
To me, that's professionalism.