As far as changes to Wayne's designs you would need to discuss that with him. The new Two Pi's use the Vifa 25 tweeter which is a nice smooth tweeter. Not a huge amount of definition but eminently listenable. However you did specify reference quality in your original post. Thats a whole new ball of wax. If you liked the Thermionic Pi's then you will like the Pi 2's and they are efficient and have a much narrower footprint but they are pretty tall. My take on Pi's is that they are the best bargain in audio; but reference quality means something else to me; something that you won't get for the asking price of a Pi speaker. You will get 90% of it though for next to nothing. Considering that Spendor SP 100's cost 4500$ or Maybe the Pi top of the line would do but they are up there also.