As I wrote above, we purchased a Surface Pro 3 (i7-256GB) in the first couple of days of August, but unfortunately the Wifi device inside the tablet seems to be seriously malfunctioning to this day and after this week's firmware update.
While the hourly resets have stopped, the connection is running at extremely slow transfer rates -- sometimes much slower even than the slow "speed" described in the "Wi-Fi Status" window.
Compared to other laptops and devices in the same location the Surface Pro 3 is very slow. For example, the Surface Pro 3 shows 24.0Mbps, but the laptop (a 2005 Dell Vostro) was experiencing no issues and was running at 130 Mbps.
Our test network was a Verizon FiOS setup using the Actiontec MI424WR-GEN3I router in 802.11n only mode.
As stated before, our Surface Pro 3's lot number/date is 1428. All firmware updates and windows updates are installed as of 12 September 2014.