Positive:
Simple and does what it says for free.
Multiple languages and voices.
Can even recognize foreign languages automatically for whole article.
Allows to use your favorite text to speech engine (google, MS,...)


Neutral:
Premium is done without affecting main functionality.: As developer myself, i understand necessity for monetization. So "selling" premium voices for premium fee is understandable and it does NOT affect functionality of free version at all. No rational person can objectively complain here.


Negative:
-1 start for it to be not loud enough compared to other sounds. e.g. Youtube is much louder. E.g. using "Read Aloud" to read article than watching streamed video makes video uncomfortably loud due to previous volume adjustment near silent "Read Aloud" sound.

I miss play/pause button and indication of read text on screen. It can be temporarily called out but disappears when not in focus.