I get a lot of shit for not giving straight answers... just spin up an instance, put a gig of data on EBS drive, snapshot, create EBS from snapshot as if you were recovering, and try pulling 100+ megs of data off it... you'll never not keep EBS copies again. big clue: pre-warming

it will take you an hour to do, and you'll be years wiser

this is probably the number one reason people experience extra extra downtime when suffering from rebuild from whatever issue... and EBS volumes in certain regions can and will experience silent deaths