I wrote a browser add-on that uses rapid serial visual presentation for quickly reading article-form content. It's got a estimated reading time feature in there that's literally based on how long it'll take to play at the current speed. I use it sometimes to estimate an article missing that metadata. It's set at my own speed preference by default, so i can quickly launch it, see the total time, and use that to gauge my interest.
https://ino.is/stutter