Hey ranph

1) I chose to clone to my internal SD so I could still swap out my external card for file transfers, switching between cards and so forth. The only advantage I could think of for cloning to the external SD is the amount of space. (internal 2gigs, external up to 8 gigs) But I personally would suggest internal

2) The debian chroot is a completely separate operating system that you can install to run alongside your normal operating system.

3) cloning with penguinbait's .deb is pretty safe. Nothing is ever a 100% guarantee, and there is a small chance that it will mess up your tablet, but for the most part, you just download the .deb and install in the application manager and you're good to go

4) No, you do not need to clear your flash. In fact, the new app you just installed will be copied over along with your operating system.

I hope this helps