[RyanZAG]

When running a search, ES by default will not show items that have been indexed in the last 1 second. Directly getting an item by its ID doesn't have that limit though, and you can optionally set a search to force a re-index and show all items.

Other than that (which is just performance tuning, really), ES matches mongodb feature for feature, and obviously has a lot of extra power from its search heritage such as facets and percolate.

So I can't actually think of any limitations, and it's why I said ES makes a better MongoDB than MongoDB.