Even if the upgrade version is free or very close to free I will probably still buy a full version. I played that game before. In the days of Dos/windows 3.1 - Windows 95/98/me i had upgrade versions and it was nightmare. You had to install the oldest OS first than upgrade it through every OS ever made. You have to keep all the media together in a working state and keep track of all your product keys. At some point my time is worth more than the 50 bucks I saved. At least let it be like office where I can just drop the old disc in to show I own a qualifying version.