That’s the Mx770 at $450 https://www.sonicelectronix.com/item...Xv3-SG-TK.html
Here’s the M880 at $1050 https://www.sonicelectronix.com/item...Xv3-SG-TK.html

I’m going to give the MX770 a try for price reasons. Running one M600/6 to power (4)MX770s and (2) M880s. I realize this is not ideal and I will not reach full potential on the 8.8s. But I’m not a huge audio guy and can’t swallow 2,500 for an amp and 8.8 tower speakers right now.