I heard the Box

True, but after the initial thrill of the different sound that electrostatics and other panel speakers have, you later realize that for all of their considerable strengths, they have their limitations too. It's all about the kind of colorations that you can live with. 

Honestly I think you get used to the sound of the box listening to so many box speakers throughout your audio life.  I never thought I could hear the box until I finally purchased spatial audio x5 open baffle speakers.  Once you hear a properly designed open baffle speaker it's hard to go back to a conventional box speaker for me.  YMMV but I know I will most likely never go back to a box speaker.  

@roxy54 , The only limitation a modern ESL has is in the very low bass. They will do it but it knocks the wind out of them. With subwoofers it is a whole different story. Not only will they go louder than most systems but they are as dynamic as any horn system. 

I think most of us who have been smitten by line source dipoles are loth to return to "box" speakers. After switching to ESLs from Allison 1's in 1978 I have never looked back. Since, I have had Tympanys, Apogee Divas, Acoustat 2+2s twice then my current Sound Labs where I plan to stay for the duration. 

I think if you start with a speaker as good as the Maggie 3.7i you will never look back. If you want more volume there is the 20.7 followed by the jump to Sound Labs. Less expensive dipoles and open baffle speakers have compromises that might make enclosed speakers preferable to some. Also, the science behind enclosures has advanced dramatically in the last 20 years. There are some very good point source speakers out there. 

Research "Tekna Sonic" vibration control panels. These devices stick to the sides of your boxy speakers and convert vibration into heat.
Long out of production, these need to make a comeback.

That is why some companies go to extremes to ’eliminate’ enclosure’s effect (i.e., Magico)