On a related note, the React docs were very misleading when they stated the following:
"In practice, finding a key is not really hard. Most of the time, the element you are going to display already has a unique id. When that's not the case, you can add a new ID property to your model or hash some parts of the content to generate a key."
I tried following their advice and used the unique ID of the search results record and it turns out that was the wrong thing to do. It was better to use the index of the current iteration and I think that should always be the recommended thing to do given the performance difference.
I agree there could be a little more clarity in that block of text, but I think the trade-offs section describes it well. Additionally, if there are any nodes in the tree that have a chance of being the same item between renders, you're going to benefit immensely from implementing a `shouldComponentUpdate` in your `SearchResultsItem.jsx` file.
React certainly doesn't win on every performance level, and if you try to compete on performance you're eventually going to lose. A careful developer could implement this list with no framework at all and have performance that beats both.
If Marko works well for your team and you find it easy to get new developers on board and contributing code then that's awesome, keep up the good work.