I use this feature with the old wikitext editor.
- It loads significantly slower than before, which is annoying. However, it is clear to me that parsing wikitext must take some time.
- The plain wikitext editor has a very useful feature: wikilinks can be followed by Ctrl+Click, so that I can look them up while editing. This is missing in CodeMirror and now, during this test, I'm recognizing how much I have relied on this possibility.