For $40 I say go for it!
My first humi, a 150 ct., came from an eBay auction.
Turned out it's a Thompson, and after I made a gasket
to seal it better, it holds rh very well. Used it for 5 yrs. now.
In fact, I use it for my high end Fuentes, like OpusX,
Ashton VSG/ESG, Anejos, Don Carlos and...