The main problem with these speakers is that they many need a continuous supply of ionizable gas, such as helium. The plasma has a by-product which we all know: Ozone, and if left in a closed room for long perios of time, it can reach hazardous levels!
Deal breaker right there if I ever saw one.
If they spring a leak you sound like PeeWee Herman for the next few hours. If you listen to them too long...you die. Great sales pitch right there.
And remember the old addage; speakers can only be as good as their source. You need some real high quality stuff to take advantage of these methinks.