All use of an HDD produces wear. Personally, I would do what I want installation-wise. HDD's are cheap enough--certainly not so costly that having to replacing one (and they don't fail that often early-on because of simple use) should keep you from installing your system many times for whatever reason you want. Of course, things can get more expensive on a laptop rather than a desktop. Whatever, I say install to your heart's content; the odds are that your HDD will last a long time.