Pretty sure
@lovinthehd uses a pair of JBL 580’s(towers) for side surrounds maybe he can add. As for using towers as mains, and possibly sides. They’re usually easier to drive than many BS speakers due to their efficiency, or higher sensitivity. They can also spread the thermal load between drivers. Ime they usually have more dynamic range, and when pushed will sound more lifelike. In other words they’ll present the scale of a room or instruments better, including the range above the XO. Still subwoofers are critical with towers or books.
This is debatable of course, but that’s mean my experience over the years with towers and bookshelf speakers.
Also imo towers look much better. Of course NOT all towers are included in this post. Some are just BS speakers with built in stands. Gross…