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We generally recommend keeping all of that content on the website, there are only a few cases where you would want to remove the content (for example if there are copyright or legal issues involved). Your site, over time, will become larger, and this is a good thing. Fashion trends tend to come back, so in 5 or 10 years if you still have that content on the site it may become relevant again. And, if it's been there for 10 years then there is a good chance that it will rank well--because it's been there 10 years and it's trusted.

I did run a search on our old pages in the SERPs and found a large number of them are still showing. I also found most of our new pages, some where both the old and new were represented. I have also seen a lot of our positions go from page one to not in the top 100, these are all from pages which were 301ed to a nearly exact replica in the new version. I had originally thought Google had hit them, but not updated their listing to the new version. I am now thinking that they are just being ignored, and have not had their 301 picked up.

This was exactly what I was looking for. Thank you very much you have really helped me out.