Any privacy concerns with using the futo-whisper open source voice library?

I was able to add their apk repo to Droidify, but am hesitant to install Futo Voice Input. Although it looks like it integrates nicely with OpenBoard.

The other option is to install Sayboard, which works with the native Graphene keyboard. Although OpenBoard with Futo Voice looks like a more streamlined experience, IMHO.

Any thoughts on privacy here?