Safestrap has a custom TWRP. It can do partial nandroid backups. System, data, and something I can't think of right now. Not a full nandroid though. Those can be restored as well. However restoring the same things from a regular nandroid to a SSd system will render the slot useless and will require deleting the slot and starting it over.
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Lost in a paper bag again...
Epic 4G Touch
If you can't follow the rules, I can't help but tell you how wrong you are.
I am the enforcer.