Pros: This upgrade installation worked flawlessly and installed quickly. I was upgrading this on a Samsung 700T which went as smoothly as any clean installation has gone.

Windows 8.1 is a much different UI, and handles several things better on this specific device than the Windows 7 64-bit it was replacing.

Cons: The only con I have to mention is the out-of-the-box experience of Windows 8.1. Microsoft was a bit quick on trying to get everyone using the Metro UI that they forced some pretty drastic changes on their user base.

If you look around, there are a lot of areas that you can bring back some of those key elements that were helpful from XP and 7 in the past.

The other thing that I've found abysmal in the new version is the networking changes. The long-standing controls that existed in XP and 7 for administrators is gone in Windows 8.1. Trying to manage networks is quite a pain, and I hope that Windows 10 will address some of the shortcomings here.

Other Thoughts: The only thing to be aware of is that there will be a slight delay from when you purchase the download and when the email with the key and download link arrive. Plan on about 5 minutes or so for order processing and the email arriving.

Pros: n/a

Cons: I was trying to download a legit copy of Windows 8.1 so I could boot camp it on my Mac. Unfortunately, this is not a digital download for Windows 8.1. It is an installer that is only able to be run on Windows 7 or later. I should have read the reviews first. Total waste of money and time.

Note: You don't even get the product key in the email and customer support won't give it to you.

Pros: NONE

Cons: WARNING WARNING WARNING
You can only perform the download on a machine running Win 7 or higher!! Since I was building a new system (everything bought through Newegg) I thought you could download the ISO and burn a disk. NO NO NO. Newegg gives you a "link to a lightweight installer/setup bootstrapper" from Microsoft that only runs on Win 7 or higher. Newegg customer support basically laid the blame on Miscrosft. No refund, no media, no help. Would have given a 0-egg if that were possible.

Pros: The OS is fine, despite the popular backlash.

Cons: By purchasing the download product you will be stuck with the bit version you already have. I.e. if you are running 32 bit and want to go to 64 bit you won't be able to get the 64 bit install image this way. You MUST download from a 64 bit OS to get the 64 bit image. This is a huge hassle, if you are on 32 bit.

Other Thoughts: Newegg should warn people about limitations with the download offering.

Pros: Very nice and smooth install - all my apps and hardware work, social media accounts, XBMC, admin tools, my older apps - all work like normal. Only had to use my mainboard's drivers for its special features - which people should do anyways. I like the new interface - always have from the start.

Cons: None found yet - but any new OS - ANY OS, will have some issues to resolve on release. I do not understand the fuss over the start button or doing things the same old way. If you want Windows 7 features - stay with Windows 7. It is a perfectly good OS. Anyone who puts a new OS in a work environment right away, is not using all their marbles or really likes to create problems for their customers....or both.

Other Thoughts: Tip1 from an experienced OS lover - never do an in place upgrade. Back up your data - and know how to restore it. Better still, buy a new hard disk and start with it - and introduce your apps and data freshly to the new OS, with all their own updates. If you cannot do a fresh install, then you are taking your chances. This goes for whatever OS - not just Windows.
My system is a custom build with medium to high-end parts and lots of external devices.
Tip2 - do your homework, know your hardware, and read the instructions. Microsoft has plenty of info online for free to use. OS installs/upgrades are not for normal PC users.

Pros: It has a start button

Cons: Most problematic OS since vista

Other Thoughts: Windows 8 was STABLE. 8.1 is not. It's that simple. Maybe I'll put it back in after a few updates, maybe not. The very few people I know who have been able to get this running without massive problems are happy with it- but that's a low amount as of this date.