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I keep everything. They will never expire. Unless I really do not want a conversation, I don't delete any message.
 
you can't see them in the cloud

you have to restore to see or use a third party iMessage extractor
 
yes I meant as save them to the cloud so you can see them all
Message in iCoud does not work that way. iCloud does not have a web interface to even view iMessage, let alone SMS.

You still need an iPhone to see them all.

Plus, I don't see the point of saving messages to the cloud just so that you could see them all.
 
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