Of course, a quick and easy installation is not much use if nothing works, but fortunately Ubuntu performed flawlessly with the X300. We've had an issue in the past with an older version of Ubuntu and an old laptop, where the drivers failed to recognise the integrated Wi-Fi, rendering the machine fairly useless. There were no such problems here and we were online in minutes.
The installer even found the integrated mobile broadband modem and Bluetooth was also discovered, though for some reason it defaulted to this after every reboot. It even recognised the built-in volume controls. All in all though, Ubuntu felt like a comprehensive and polished OS install, and did better than Windows 7 beta on the same hardware.
It wasn't all peachy though as after a couple of suspends, it failed to find the Wi-Fi again and only a reboot restored connectivity.
Also, we've seen various reports, and one from our Ubuntu 9.10 Karmic Koala reviewer, that it doesn't seem to like some ATI hardware from a few years back such as a Radeon 9600 card. As with all such things then, Your Mileage May Vary.
That said, as we wrote this, our Windows 7 laptop experienced a crash in its integrated graphics drivers, from which it recovered, but it's a clear sign that Windows 7 is not completely bullet proof. If there's something Windows-only you want to run, you have a good chance of doing so under WINE, special software for Linux that lets you run Windows apps.
While we had a very good experience with Ubuntu 9.10, it seems reasonable to say that Windows has the compatibility edge overall.
Winner: Windows 7
