We visited Wasabi in Constantia for a sushi feast with a few friends, and at this occasion I learned one important lesson about eating sushi out:
Pay full price for your sushi and never order the sushi platter that's on special. :)
This particular platter cost about R100 and seemed to contain all the small offcuts of salmon and tuna, as well as many vegetarian pieces that, judging by how dry the carrots appeared, weren't very fresh at all.
I ended up eating just over half of the platter before realising that I really wasn't enjoying it enough to continue. From the way the other folk at the table devoured their meals, I assume that the other sushi must have been good; but this was presumably because they didn't order the platter that was on special. :-/