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Hi, We have 4 foreign language sites, one in spanish and just remove the special characters in all and rank very highly, so there is no harm in doing this, it actually makes it harder. I would stick with all lower cases or at least have the same logic in the URL - as long as it is consistent, then no biggie. No matter what you do, make sure if you make changes to any of this that you 301 all of the old pages to their new version otherwise you will be starting from scratch! Hope this helps.