I think most games, the installer wont be deleted, thats y taking up so much space.
I think can tinker with the setup files after install, but too bothersome.
like the other day, I deleted CoD5 demo (lol, bought game also dont delete demo)
and found out the space cleared is twice the space occupied by the demo.
meaning the installer didnt get deleted after I installed the demo, and only get deleted after i delete the installed demo.

@shawty

I think that article is a bit old, no ?
You can search digital foundry for the latest ssd related test for consoles.