I just downloaded the full 8 disks for Omnisphere 2 and I'm thinking about uninstalling Omnisphere 1.5 prior to installing. Once I install Omni 2 will all of my old projects open with the presets I used from Omni 1.5?

 

Actually you do not have to uninstall 1.5. Version 2 overrides it with no problems and everything is retained

 

I understand, but the reason I want to uninstall 1.5 is because I don't have enough storage to install 2.

 

Space is not an issue, the version 2 installer over rides the older installation, IT DOES NOT double up the space because everything goes to the same folders, The only thing would be the extra added content from v1.5 to v2.0. It's just an update NOT a full new installation. Now if you are worried about the space the 8 disks take up and also the space you have on your drive. Take your time and install one Disk(iso) at a time and then delete it, move on to the next one.