We always install a new OS on a separate drive inside our Mac Pros so we can easily switch back and forth between the OS' just in case we have a major issue.
Currently all our machines still have their "Leopard" drive so when Lion comes out, we'll erase those drives and switch them over to Lion. Makes it really nice in case all heck breaks loose, we just re-boot to the older OS.
Walter Biscardi, Jr.
Editor, Colorist, Director, Writer, Consultant, Author, Chef.
HD Post and Production
Biscardi Creative Media
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