Sigh.
I wanted to love this place... I've given them several tries and am sad to report that the only thing in common with THE Katz's Del (of New York City fame) is a name and a highly diluted culinary cultural heritage.
This is a cafeteria style deli that has all the right items on the menu - but they're all done wrong. Perhaps I should say RE-done wrong. Microwaved Latkes? (potato pancakes) Are you kidding me? Nuking a latke is tantamount to nuking a double espresso - both are culinary hate crimes of the highest order. These should be punishable by a one month sentence of nothing but pizza-pizza.
The corned beef is certainly edible, but lacks the flavour and pop of the good stuff. Frankly, it tasted a bit old - the steaming here seemed designed for longevity enhancement rather than flavour. The smoked meat is mega-meh - just go get some at Costco if this quality is sufficient for you.
Aside from the garish design of the space (I'm all for re-purposing, but this IS supposed to be a deli...) the place has a whiff of authenticity. There are just better choices in the GTA