Planars/ Electrostats benefits over box speakers?


I always been fascinated by Martin Logan and Magneplanar speakers. I have heard one or two models of both over the years. Would like to get some input from owners of "planar speakers" as what sound quality benefits do they offer over a floorstander, especially in the area of overall smoothness.

Are there any planar models of either company that have a small footprint and are not monolithic in height, but still sound very good???
sunnyjim
Shameless plug:

ES/planar fans, I have my STAX SR84 Electret phones up for sale here if anyone is interested. You won't find that planar ES sound for any less than these anywhere. Plus they work well with most any amp.

Why am I selling these you ask? I am in process of clearing out some of my older currently unused gear that has value. If they don't sell I'll probably set up yet another system in the house with them someday, maybe running off a SET amp.

http://app.audiogon.com/listings/over-ear-stax-sr84-lambda-pro-jr-earspeakers-and-15-foot-extension-cable-2015-07-03-headphones-21136-reisterstown-md

BTW the other STAX up for sale on this site currently are all 10X plus what I am asking for these. These sold for $300 back in 1998 or so. I also have a long STAX extension cable included to make listening possible from most anywhere in a room.