This is  my next question, sorry if anyone feels I'm flooding the forum, but I wanted to keep them separate.
As I said on another topic, I just upgraded from X2 to X3. Unchecked everything I knew was already installed in X2 and only needed the first disk to do it.
I think I expected it to overwrite X2 where necessary and leave me with just it. What it did was install the new version alongside of X2. So my question is simply should I have unistalled X2a completely (making sure to save my project files first)?
(Just for better organization and minimalization sake.) 

SONAR never overwrites previous versions of the DAW. It will overwrite/update plug-ins and utilities. The non-shared parts use up less than 200MB. You can uninstall X2 if you wish but V-Vocal, R-Mix and other plug-ins that are not part of X3 will be removed too. Of course, you can get them back by performing an advanced install of X2.

If you have the room, I recommend you install X3 and keep X2a installed as well. They run independently, and you may find need to refer back to X2a at some point.
 
Michael

Have you ever used one as a rewire into the other?
(If that even has any use or advantages...)