All of the chests in cloud ruler respawn except the one labelled "Armory" in the armory, which is safe.
thanks for the help..
Most likely, yes. If you want - although its rather tedious - make a save with the items in the crate, wait 72 in-game hours, and if the items are still there, its safe.
http://www.uesp.net/wiki/Oblivion:Safe_Containers#Safe_Containers is a list of known safe containers in the game.
thank you also!
im gonna use the first quote, and the 72 hour thing and test out the 'armory' chest.
thanks again for the help guys!