Starting off with the default voice I felt it will be a 1 star rating. I went through many voice options and they are pretty much all robotic and of low sound quality. The real slap in the face occurs when selecting a Google standard voice, you need to grant extra permissions which is fine and you are redirected to Google's text to speech site (https://cloud.google.com/text-to-speech/#put-text-to-speech-into-action)
The voice on the Google site (wavenet-d) is what most people would enjoy, very natural and of high sound quality BUT it is not what you then using this addon.
This addon does what it says on the tin, >eat bean every day 8-/
Fad/Fart

The add-on is great and overall it works very well. You can customize the speech speed and pitch, stop, and rewind it. That said, it does have an issue on some linux distributions where it crashes the pulseaudio driver (but not all). It's not clear why this happens, but when it does the driver has to be restarted and then the plugin doesn't work again until a reboot. It's a bit of a niche problem so I only took off one star for it. That said, I put in a bug report for it and have heard nothing back from the dev despite a patch being released after my bug report.

LOVE THIS BROWSER!

Text to speech voice is too robotic, it gets tiring very quick

Good when it works, which is not often.

Can't go a single day without google's voices breaking and requesting to "grant permission/admission" from google's TTS page.

Este complemento está muy interesante

It works fine but it could be better. My only issue is that it doesn't read some math symbols properly, which is the main reason I installed this extension.

Top TTS reader imo. Amazon voices are now great. Couple problems I've encountered are inability to edit shortcuts (though there's a page for that) and no speed control on the fly. I would also appreciate text highlighting to be more precise. It's hard to find what you're looking for when the whole paragraph is highlighted.

Very computer-like voices and not much better than the built-in TTS feature which is built into Firefox.

it works but its super buggy. sometimes when i skip a paragraph it highlights the paragraph beneath it. and sometimes when i press stop it continues talking.

No tenia ninguna expectativa sobre esta extension, pero realmente me sorprendio.
Me gusta mucho anda bien y las voces sinteticas son agradables.
Gracias por compartirla!!!