Yes, I like to have ISOs of games I own on the Hard Drive to save on wear and tear, and I also like to back them up in case the original CD "dies". I haven't had a CD do that yet, but I had to resurface a few, and you can only do that a number of times before the CD is ruined.
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-Dreams of getting a new 360 XBOX in 201x.
-Current consoles: Playstation 2 and Wii, also has DS/GBA and a PSP 3000
-PC: AMD 5000 2.6 Dual Core, 2GB Ram, 8600 GeForce GT video card, SB Live!, Win XP SP3