It does have a cab sim on my Superblocks 25 UK and US. I'm really happy with mine. I plug into one of two 1x12s that I have, one with a Celestion Redback, the other has a Scumback J75.
Have yet to gig with one, but I've had them at the practice space, and they sound great for my needs. Great crunch via the MV set up. I haven't tried clean at volume, alough it sounds good at lower volumes.