I've been running 2 Bogner cubes with EVM Black Labels. Sounds amazing, but I'd like to mix it with another speaker. I am thinking about adding 2 more as well, with Scumback 75s. Not sure, maybe just one of each. But I have cranked my Wizard and SLOs through these, I mean cranked, and they did not fart out. Simply amazing to me.
I have a Mark IV with an EV loaded Thiele cab and a Mesa 1x12 open back cab with a Scumback M75/65...sounds awesome! I used to have an EV in the open back too and while it was a clearer speaker, the scumback added a lot of warmth.