I installed it on my older Vista laptop. I'm actually very impressed. The laptop is a Toshiba Satellite A205-S5804, which is a total piece of crap, really. Vista hardly worked on it because of that memory leak with the updater. Even after I disabled the updater service the thing was still pretty slow when running Vista. So, I installed Windows 8 along with Vista on it. Windows 8 boots and shuts down incredibly quickly. It runs so much faster and smoother than Vista. It's actually a usable computer now. In fact, I'm using it to type this post right now.
As far as the new UI, I don't mind it. Actually, I find it very easy to use, even on a laptop with no touch screen. Switching apps is easy and you don't have to cycle through them one by one. If you throw your mouse into one of the left corners then move it up or down along the edge of the screen, you'll see a list of all the apps you have open. Click on the app to open it or right click on it to close it. I've had no problem finding things such as the Control Panel or Disk Management because of the search option. Throw your mouse into either of the right corners to open a menu with Search, Share, Start, Devices, and Settings. The Search feature works very similar the old search feature in the old start menu.
I can think of one complaint, though it's very trivial. Scrolling in the apps is not consistent. On the Start menu, you can push the curser against either edge of the screen to scroll left and right. That's all well and good, but, in other apps, that doesn't work. In some apps, I can scroll with the trackpad on my laptop. That's great, but I can't do that in the Start menu. Some apps, the trackpad won't even work. I must move my curser to the bottom of the screen and use the scroll bar. Any programmer should know that consistency is a good a thing.
As I was typing the last paragraph I thought of another thing. I can't figure out how to very two apps side by side. That was something that Microsoft showed in their demo that I kind of liked. When I try to drag in a second app from the side of the screen and hold it there, nothing happens. Also, if you move your curser to the top of the screen while using an app, you can grab the top of the screen and the app gets smaller and you can move it around but it doesn't appear to have any purpose.
Overall, I'm impressed. The Metro UI makes it easy to get to small apps for quick use and it's still easy to use full applications on the desktop. I've gotten use to using the corners of the screen to control the new UI and I actually find it very quick and easy. It'll be even better for tablets because it'll run faster and easier than Windows 7 and it'll be able to run full applications unlike iOS and Android. If I have the money to spend, I may consider getting a Surface tablet. They look pretty sweet
