It is difficult to determine the best AI-based TTS text-to-speech and voiceover software as it largely depends on individual needs and preferences. However, some popular options include Speechelo, Speechify, Lovoai, and Deepgram. These platforms use advanced deep learning techniques to generate synthetic voices that sound incredibly natural. They offer a range of voice options across multiple languages and have unique features such as the ability to add breathing noises and pauses to make the speech sound more natural. It is recommended to try out a few different options and compare the quality and features to find the best fit for your specific needs.