Hi Victoria,
I have an SD card in my display, but I just don't use it. MyAcuRite and WU are giving me all the look back that I need. As a Chromebook user, I would have to upload the SD card to the Google cloud if I wanted to do something with the data, as Chromebooks do not themselves play nice with .CSV files.
I also believe that opening up user data to multiple services could be a very good thing. One risk of course is that AcuRite might see more support demand, much of which should probably be directed elsewhere. Like today, when WU hiccups, and you get the calls!