I purchased a set of Davis instruments, which includes Wizard III and Monitor II. Several accessories came with it. I’m wondering how it compares to the WIFI stations that require Weather Underground to connect. Any thoughts or advice?
I should include that I intend to use it with Weather Display software directly, instead of relying on an API
I think you have made a wise choice, even though I have never heard of Wizard III or Monitor II.
I presume the Davis is WiFi, too?
No. Actually it has cables to hook up to the com port on the computer. My current station has to connect to ProWeather Live, then the data gets sent to Weather Underground, and back to Weather Data. I’m looking for a direct connection to get away from all that.
Even better choice 
They’ve been discontinued for some time - I don’t know the availability dates, but they were definitely selling them 25 years ago. Davis gear is well built and keeps on working though. The problem might be getting spare parts if you do get any failures. Beyond that, other than having heard their names, I know nothing about them.
What I have now is a Logia 7 in 1, with every sensor available. What Amazon lists as a 21 in 1. It’s a WiFi connection. It runs steady. I’m not too confident with the accuracy, but it was a bit pricey so I hope that means something as far as quality goes. But I still think a direct connection is hard to beat.
That’s what I’m counting on. Something built good with dependable accuracy. Our rural area is too far from the big cities that have forecasts geared towards their area and not ours. We had an eminent dam failure watch for the first time in the history of our lake, which is one of the biggest in Texas. We also have 259 families that had to be evacuated after flooding had begun.They were relying on the forecast of a city that is 100 miles away. Without accurate weather data, we may not get enough funding allocated for disasters here.