Have you compared it with a CoCoRaHs type gauge? I was shocked at how inaccurate my VP2 is.
No I haven't but it was something that crossed my mind last night. I am that type of person that likes accuracy...
As an update, we've had light showers all night. Except for one brief period at around 12:30 AM where it recorded at 0.02"/hr it has recorded .01" of rain just about every hour this morning. If you look at where I live, Bakersfield, CA, you would know that we do not get much rain. 5.28" is what I saw last calander year. I live in the foothills, so I get a little more precipitation than the valley floor does, but I am sure there were many light showers last year that I did not record any precipitation when I should have with better equipment.
You can check out my data on wunderground as I am not supporting my own web page at this time. My station ID is KCABAKER21.