Sherpa links to this page, if anyone wants to preview what the voices sound like
https://huggingface.co/spaces/k2-fsa/text-to-speech
From the ones I've tried so far, csukuangfj/vits-piper-en_US-amy-medium|1 speaker sounded the most clear and natural for GPS / driving directions. If someone finds other good ones, I'd appreciate it :)