I have a brand new drive in an enclosure that I want to install Lion to. I made a boot disc and USB drive to do this. My plan is to install Lion onto the external drive while keeping my original hard drive in my MBP with SL. My main question is: Would it be ok to install Lion to a USB external drive? Later when Lion gets all compatibility issues settled, I plan to switch the drives. Would this be done with no complication? Also should I install via USB or DVD?