Coming into the discussion late:
I am still using the legacy version just for the tag feature, which was completely messed up in the new version. No search solution will replace a simple OR feature for a tag hierarchy. For example, suppose I want to work on filing AND daily tasks AND weekly tasks today. I drag the tags "filing" "daily tasks" and "weekly tasks" under my Today tag. I then select Today and it gives me all the notes that are tagged Tuesday OR "filing" OR "daily tasks" OR weekly tasks". I may have three dozen tags under Today, some of which are further down in the hierarchy.. To build a search for each of those is time prohibitive. In legacy, there was no search at all. I just clicked on the Today tag and had a complete list of notes with ANY of the tags under Today (an OR search), giving me a long to-do list to work off of.