Bests & Worsts Reviews from Amazon

I made this comment (now edited) to someone else's review, but for potential buyers, seems like it ought to be a review of its own: For me, upgrading to Vista from the factory installed Windows XP Media Center Edition didn't work as promised. My system is compulsively up-to-date. I ran the Upgrade Advisor from Microsoft AND from Sony, and both said my system was fine, good-to-go. Upgrade away. So I inserted the Vista Home Premium Upgrade version disc, but it wouldn't install, kept shutting down, requiring that I input the Product ID over and over and over, not getting past 21% of the Expanding Files section. A post on one of the Amazon boards mentioned NOT inserting the Product ID until after the installation and selecting the Custom instead of Upgrade option. Oddly, that worked. Vista installed. It is a beautiful thing. I want it. Someday I hope to have it. But it wouldn't activate, said I had to have the full version Vista Home Premium, not the upgrade version. After scanning my system, it couldn't tell me that during the "Advisor" stage? Resigned to a quagmire, I took the upgrade version back to the store (CompUSA). They wouldn't accept it (no returns of open software). Bright light of hope, the tech manager PROMISED that the Home Premium Upgrade already in my hands would, in fact, work fine on the factory installed XP system. (His name is Abel, but I think maybe he isn't.) All I had to do? Restore my computer to factory condition (Sony VIAO desktop RA910G) then reinstall the Vista. Since all the updates, drivers and files were current, with documents securely backed up, I decided, what the heck -- worst thing that happens is my computer is fresh and new. Not exactly. Same boat. And on top of the Vista STILL not installing, I have my computer back to factory condition, meaning that years of security and software updates are re-required. The snazzy Windows Media Player 11 that once managed all my music and videos won't upgrade beyond Media Player 10, ergo, the music download company I use (URGE) won't install into my system, ergo, aaaaargh, I have a cramp. I haven't even reloaded Photoshop or my working software yet. I'm feeling another day of headache (going on 18 hours of actual involvement at this point with more to come). I hope someone can offer a helpful solution. I can't find one at Microsoft's site or via Google. Although my computer is more or less in working order, Windows Media Player is downgraded and Media Center doesn't open at all. My entire system is less than it was and that's unacceptable. In the meantime, I agree with others that although this is a very beautiful product, the WOW factor could be described in less enthusiastic terms and late in the evening, in more colorfully expressed four-letter terms. UPDATE: It finally works, a lengthy and frightening experience all around, but with so much trial and error, I found the combination that worked for my system and maybe yours, if you're having the same problem described above. See INSTALLATION & ACTIVATION: FINALLY in the Customer Discussion area for this product.