So a good workflow you might be interested in is I copy all my lossless tunes (I buy lossless then convert to .mp3) to my external, then I have PN go through a folder where the downloads sit, cut the new files (I have Pn set to add _PN to the title of each song) to the same folder I store all my Rekordbox mp3s, run MiK on whatever is new, then simply add to my collection in Rekordbox.
Or Tl;dr: PN>MIK>Add
To Note: PN & MIK will eat a lot of resources, mainly your CPU, so I’d advise doing all this before a show, not while you’re trying to Dj. Also, MIK requires an active internet connection to analyze. MiK also has a tag editor that’s actually very good. It gets very confusing to try to explain, but suffice to say: Make meta-data changes in RB so that they stick, not in MiK where you would have to add the file every time you made a change. While the tag editor is great, it probably won’t get them all if you play a lot of underground stuff.
As for if you can tell if PN worked or not, it’s hard to tell but if you do a side by side (Either in a daw or by listening to a tune you know really well), you’ll hear it then. But there’s no real visual way unless you have PN do the same thing I did.
Let me know if you need clarification for this.