I just had my v3 SD card plugged into my PC this morning. I have my resolution set to HD on the v3 camera and my 1-minute video clips were less than 7MB each. Therefore I would say that you will get roughly 3-days worth of video on a 32GB SD card with the resolution maxed out.
Below is some simple math with VERY rough numbers. Keep in mind the useable space on the SD card is far less than 32,000,000,000 bytes. Also, the HD videos are less than 7MB. With that said, this will get us close enough to answer your question.
32,000,000,000 (bytes on SD card) / 7,000,000 (1-minute of video) = 4571.43 (minutes of video)
4571 (minutes of video) / 60 (minutes in an hour) = 76.18 (total hours of video)
76 (hours) / 24 (hours in a day) = 3.16 (days of video)
Have a great day!