I owned the original Spatial M3 Turbo S. It represented a terrific value, and offered great sound for the money. However, they don't really do bass the way you're describing. In my open floor plan home I needed to employ (2) 15" subs and a sub EQ to get somewhat realistic bass. While I owned them, I also seriously considered adding many room treatment panels because I felt the speakers demanded it.
I'm still a Spatial fan, and wish I had a room they worked well in (small, well treated, long but narrow, and with a low ceiling) something like a purpose built man cave in the basement...unfortunately I don't.
This is a long way of saying the Forte 4 is likely going to be easier to integrate into a room unless you already have the right dimensions, room acoustics dialed in, and multiple subs (for your classic rock).
@ozzy62, the LaScala has been one I've lusted over in the past but have a hard time justifying the real estate for the amount of low end the speaker provides (on paper)...I've not heard them. Are you using subs to support the lower frequencies?