NEW YORK ( TheStreet) - TheStreet.com's first attempt at installing Microsoft's ( MSFT) brand new Windows 8.1 Preview is now complete, and unfortunately it took way too many hours to complete. Nonetheless, the initial results are good. We installed the new beta software on a Windows 8 laptop and a Windows RT tablet, and in both cases the download and installation was laborious: nearly two hours in the case of the laptop and a whopping 6 hours for the Win RT tablet (it actually needed additional downloads and upgrades before I could proceeding with the 8.1 preview.) The software was officially released Wednesday morning, so by the time both installs were completed, we were only able to spend a few hours w each computer to put everything to the test. Our first impression: in both cases the upgraded operating system adds a much better user experience. Faster, more fluid, more polished. That's especially true for our RT tablet which never really worked running the original Windows 8 RT software. It seems to like 8.1 a lot more. Microsoft shares were rising 1.2% to $34.70 in morning trading in New York. The best new feature is the ability for users to set their computers to boot directly to the older Windows desktop, the screen that we have grown to love (and hate) since Windows 95. Despite the rumors, the START button has not made the return appearance that many Windows fans had hoped for. But, it now gives you a choice. Press the new Windows logo in the lower left corner and you're taken to the Windows 8 Metro screen. The one with all the boxes. Your choice, not Microsoft's. Windows 8.1's Web browser is now Internet Explorer version 11. Microsoft claims 11 is faster and offers added compatibility for upcoming (including 3D) standards as well as the ability to deal with additional page tabs. There is a new on-screen keyboard. Our first impression is it's great. At this point, we believe the Windows 8.1 keyboard to be among the best on-screen tablet keyboards we ever tried.