I do have a Wren, which is smaller than the Sparrow, and I love it! I'd be happy to answer any questions.
ETA I did also post a vid that is still on my page.
updated by @hugssandi: 02/09/17 03:43:36PM
Some time back a member posted a video of them playing one of these I think, can't remember who it was. If anyone knows who it was, or has feedback on these as far as the usual intonation etc. I remember hearing the recording and being fairly surprised by how nice it sounded