You think any of the amps that would be a "better deal" don't have the same kind of markup in Australia? They do.
An anyway the CMD121P doesn't have any serious competition in terms of volume and portability in any less expensive combos.
How does the GK MB112 compare in terms of volume and sound? Anyone out there played both? It comes in at $700 here in OZ. Unfortunately the powered extension cab is basically impossible to find over here.
If I had $1600 to spend I'd probably buy the MB112 and then source the powered extension cab from overseas (found this one for around $530 delivered from the US). You'd be looking at less cost (around $1300) and then you have the combo for smaller gigs and rehearsals and you can take the extension cab to bigger gigs. Unless you play in a loud rock band with a drummer that can't play softly this combination would cover just about any eventuality.