Just a quick tip here. Several Surface Pro 3 users that have already installed Windows 10 Build 9926 are reporting serious slowdowns and video performance problems. The problem is fixable and results from Windows 10 installing only a basic video driver for the Surface Pro 3.
A new video driver for the Surface Pro 3 running on Windows 10 was released just prior to the Build 9926 release. Go into Windows Update and grab it. But, if you still have problems with this video driver after updating, disable hardware acceleration in IE Advanced Settings.
Also, it's pretty important that your Surface Pro 3 is completely up-to-date. Microsoft released a fabulous system update this month that should be installed first. The latest firmware and driver update makes the Surface Pro 3 an almost flawless device. Read about it HERE.
Of note, one of the known problems reported by Microsoft already is that devices that use connected standby (like the Surface Pro 3) will see a considerable decrease in battery life. Just something to know going in.