I am running this code in Xamarin Forms:

        var settings = new SpeechOptions() 
        {
            Volume = (float?)0.75,
            Pitch = (float)1.0
        };
        await TextToSpeech.SpeakAsync(msg, settings);

On an Asus Z01KDA. Android running OS 8.0.0

ZenFone 4 (ZE554KL) Z01KDA @asus
6 GB RAM, 6 GB RAM, 64 GB max storage, Snapdragon 660 / Kryo 260 chipset, 3300 mAh battery, 12 MP primary camera, 8 MP front camera, screen Super IPS 5.5" 1080x1920, weight 165 g, Android, 3.5mm Jack / USB Type-C, released on 6/2017

I am running Xamarin Essentials 1.1.0

The same code is used for Android and iOS. iOS sounds good but the on the Android device the speed of the sounds is slow. Perhaps 0.5 to 0.75 as fast as words on an iPhone X.

Right now the plugin is unusable for me because of this.