Now let's say you wanted to use an app that needs most of your memory, like GTA IV if it was ported, you will run out, which is ridiculous and wrong for DE to waste that much memory. No my memory is not cheap, I'm still using old Windond BH-5 modules that run at 2-2-2-0 @ 3.45v, you can't upgrade that or put more sticks since chipset will not handle it and become unstable. In my book DE the max for i386 should be at most 100MB, and for x86_64 150MB. Maybe that's the reason why I still use XP. Win32 FTW!
I would see the compromise for using that much memory if those shitty DE gave the responsiveness of what Windows gives. Not even Nvidia drivers help or tweaked SSD disk with unregressed file systems. What sucks even more is that KDE is dead slow and sucks ass. Starting a text editor or calculator takes a 1.5s delay? To do what? WTF?