<p>I want to know if people here typically disable SELinux on installations where it is on by default? If so can you explain why, what kind of system it was, etc?</p>

<p>I'd like to get as many opinions on this as possible.</p>

I don't have a lot to contribute here, but since its gone unanswered, I figured I would throw my two cents in.
Personally, I disable it on dev boxes and when I'm dealing with unimportant things. When I am dealing with anything production, or that requires better security, I leave it on and/or spend the time tweaking it to handle things how I need.
Weather or not you use it really comes down to your needs, but it was created for a reason, so consider using it rather than always shut it off.