Keep the old content as long as it's still relevant and up-to-date.

There is absolutely no reason to dump your old text just because it was created some time ago.

Thats what I was thinking too. Thanks for the reply.

We do have to switch those texts at some point, because they are not very fun to read and not very rewarding. We want to change that. But that will be a subject for when the relaunch is done.

We are planning a big relaunch of our websites. New design, new structure and so on. One part of that was to outfit every one of our products with new texts (SEO of course). Now, our question is - do we keep the old texts that rank quite well until everything else is done and works properly and then change the texts bit by bit to minimize ranking loss? Or should we relaunch with new texts?

We are all more ore less rookies with not much experience, so any help is appreciated.