I've been testing several TTS plugins and by far this one is the best.
It has more features and options, works straight away, and the streaming voice is free.
I only found one other that actually works, and the developers of that one are dodgy about what it will cost once you are done with their free trial period. You have to email them for a custom quote. That means a pretty high number I'm sure.
I like the way you can highlight a certain part and play just that.