two small feedback pieces:
Agreeing with Marco re "Most used", also because I can see "Popular" being an i18n challenge. In other languages the word that most closely maps to Popular might have an even more different sentiment from actually-most-used.
I'm kind of confused by the settings UI. Show ... first? As opposed to what? The bottom?
"most used" is not what it does - it is a combination of most frequently and most recently used.
As for 'first', you are right. The source of the word was the possibility to show an infinite list.