Skydrive came a long way with Windows 8.1, being integrated into the OS more than before.

Before going completely "cloud" I wanted to have a mixed enviroment with local and remote files and with two or more PCs in the mix.

Having this setup doesn't seem to be a problem but one thing was always in the back of my mind: what if I need to refresh one of the PCs? Skydrive doesn't support peer to peer connections, and I don't want to have to download everything in case a PC crashes. Would it support copying files from a local backup instead of downloading from the cloud?

So here is what I've done: I have my documents inside Skydrive and these are available offline on my laptop and online only on my tablet.

I have now added my Pictures folder (by changing the location of the Pictures folder) waited a bit so the folders would appear online and then disconnected my laptop.

I connected my tablet and waited a bit so that the folder structured would appear on the client. I then disconnected the tablet, marked Skydrive to be available offline, copied the Pictures folder from local storage (a microSD card) over the local Skydrive | Pictures folder and then connected the tablet again.

The result is that all the Documents files downloading to the tablet (as expected) and the Pictures files are being uploaded to Skydrive (as expected because the laptop hasn't uploaded any yet). I then put the laptop online again and to my delight (?) it is uploading some of the photos but not downloading/duplicating any of those already uploaded from the tablet.

Cool. So the sync engine is clever enough to detect that those files should uploaded to the cloud and are available in two locations so both are uploading.

But what about the scenario I explained before? Here is what I've done: I copied 1.5GB in files to a new folder on Skydrive on my laptop. These were uploaded to the cloud and appeared on my tablet as "online only". I then disconnected the tablet from the WiFi access point and manually copied the files over. I then connected it back to the WiFi access point and changed the files to "available offline".

Skydrive showed an action for each file but instead of downloading from the cloud and overwriting the files it correctly identified the files were the same and skipped actions.

So the conclusion is that in case of a crash we can overwrite the local folders before turning then "available offline" and this will not require the files to be downloaded from the cloud.

My only pet peeve with Skydrive / Windows 8.1 is that the app should really open documents using the Office Web Apps by default (or as an option) if there's no local copy of Office installed. For example I am trying to use only Modern UI apps on this tablet but obviously Word, Excel, PowerPoint don't exist as Modern UI app on Windows 8.1 Pro. In this case when I tap a .docx document on Skydrive for example it comes with a "find program to open this file" when I truly expected it to just realise there's no local Office and just open the web app instead...