Please Recommend Highly Efficient Floor Standing Non-Horn Speaker Suggestions

A friend has some older Lii Audio Crystal single driver speakers from Decware with a Riviera Audio Labs Levante Hybrid Integrated amp, one of very best amps we heard at any price and we both love these speakers a lot. They are one of the best speakers I've heard at any price. I like them better than Cube Audio they have deeper bottom end and better total balance and are more musical engaging. This guy likes them better than Cube Audio too. Lii Audio and Riviera Audio Labs could be my end game system.

 https://www.youtube.com/watch?v=ndoUs_1MahA&t 

A few videos on the Decware Lii Audio Silver S-10's 

 https://www.youtube.com/watch?v=qVez8PTTeAI&t

 https://www.youtube.com/watch?v=ZMoVCjLN4DY

 https://www.youtube.com/watch?v=jKAk1pmWpi4

Thank you for the video links. I have pair of the Decware HDT speakers. I have ordered a pair of the Lii silver 8’s and will put them into the HDT’S. An inexpensive approach to try out the Lii drivers.

Here is an Decware Lii Audio Silver-10 review 

https://www.youtube.com/watch?v=nKcfGAnGGqw&t

Tekton Lores.  I just acquired a pair for $500 local to me.  Detailed and musical.   They sound full bodied even at low volume.