I'm digging the crown. The SLA2 is good, but it's heavy as hell at 26 lbs, is deeper than my axe-fx so it barely fit in my rag bag, and runs very hot. The crown seems to sound just as good, is only 9 lbs and 7 inches deep. Lots more headroom and also can run bridged mono at 4 ohm, which the SLA2 can not.
As far as the cab, my sound guy builds PA speakers and subs as well as does speaker repair. I was using two Alto TS112A's and missed the 4x12 look on stage and asked him how hard it would be to wire up two FRFR monitors into an empty 4x12 cab. He thought it would be pretty easy, so he disassembled two Mackie 12" monitors and installed the 12" speakers on the bottom and the 5" horns on the top, and wired it up for 4ohm mono, 8ohm stereo. It sounds fantastic. Fills space volume-wise like a full cabinet, but allows me to keep using whatever different IR's I want with different presets, and still running of the outputs straight to the board.