Sounds great.
To me that is, one thing I've learned is that what sounds like a turkey to me doesn't necessarily sound like a turkey to a turkey. For instance I think I make much better sounding calls with a mouth call but I've called up the most turkeys with a box call.
Like you say, it doesn't seem to have any sweet spots like the slate call does. Much easier to do what I want with it.
There was some admonisment on the package about only using a particular type of abrasive to dress it ( silicon oxide sandpaper? ). Any way they said if you use something else you might polish rather than cut the glass.