One issue is a performance one, I'd rather see:
+mp3 dylan
The + triggers FARR into knowing there is a search modifier, so turns progressive find off, then once the text is typed FARR can search directly. Otherwise dylan +mp3 will keep hitting the hard disk on each keypress through all folders until FARR parses the final +mp3 — this is highly inefficient, especially if the search modifier is set to a single folder.