Product review (1 stars): Perfect for almost 1 year -- then circuit board failed; Emailed Golden Vantage and got no reply.  Would not buy again!
The title says its all.  It failed exactly like other posters said -- pressing the buttons (light, +, -, auto-sensor) do not invoke the corresponding actions.  Then I saw it turned on automatically (I guess the auto-sensing function was on, even though its light was off on the panel) when trying to boil some water on my stove.  Now I have the power unplugged.

Emailed Golden Vantage support and did not get any reply.  Sigh.  Would try to call them again, but my hopes are not high.  Right now I would recommend anyone to avoid this brand and vendor.