Thank you for these links. At the risk of embarrassing myself, I'll share my experience, in case anyone is interested.
Within 15 minutes of going to Amazon Polly I was creating MP3 speech files from text I pasted into a cloud portal. Very fast and easy to use.
I spent over an hour navigating the Microsoft site, going through countless intermediate web pages, often wildly guessing at what links to click to progress forward on TTS. Along the way, I learned that after 30 days of free usage, I would have to explicitly REMOVE ALL SPENDING LIMITS ON MY CREDIT CARD in order to proceed with more usage, even in the free tier, just trusting them to not charge me anything. When I finally found my way to the no-programming console page, I learned that I would have to install on my computer multiple pieces of Microsoft software in order to proceed. Their instructions as to what to install, based on my computer's configuration, were cryptic. No way.
I spent about three hours navigating the Google site, trying to find text-to-speech. You'd think it would be easy, but none of the pages were clear. I never did find text-to-speech.
Bottom line: I'm using Amazon Polly and finding it very easy to use and reasonably decent quality.
PS: I wish, as another member suggested, that Reallusion would form a partnership with a quality TTS provider. Reallusion's visual capabilities are excellent, but those of us who want to create videos in which characters speak are left behind.