Windows 10 Redstone 3 (RS3) Version 1709 (Build 16299.15) is available on the Fast Track for Windows Insiders:
Currently the best way to get it is to Download the Windows 10 Insider Preview .iso build 16292 and perform an in place upgrade.
https://www.microsoft.com/en-us/software-download/windowsinsiderpreviewadvanced?wa=wsignin1.0
Then right click the button and select Settings → Update and Security → Windows Insider Program and change your settings to the Fast Track. Although updated RTM installation .isos will likely be available via the Windows 10 Media Creation Tool in a couple of weeks.
Microsoft Edge now can be used as a proper PDF reader. Microsoft have finally supported PDF bookmarks into Microsoft Edge something I've requested since the original release of Windows 10 TH1 (Version 1507):
There is also a tab preview and more support for writing with a stylus:
Also they have put in the ability for full screen viewing: