Playing with Tortoise-TTS-v2, it's quite slow, although I tried it in WSL which may or may not have direct access to the GPU and may or may not be defaulting to CPU. I will play some more on my Linux laptop/Macs, but thanks for the heads up

Just noticed that there's a Tortoise-TTS-v2 on HuggingFace (although the last update was 2 years ago). Certainly something to start playing with!