You can do worse than hook up with friends over a business lunch at the Duke of Westminster. Like it's in-the-business-core-of-Toronto sister pub the Duke of Devon (http://www.yelp.ca/biz/the-duke-of-devon-toronto), it is a member of the Duke franchise, so you know what the menu will hold and what pints are available. So, no surprises there. It's decent, not to worry.
What will surprise you is the sheer size of the place. The first chore can be something as simple as trying to find the folks you're supposed to be dining with. There are multi-levels and many places to hide at the Duke. You'll do well to pick a meeting place outside of the Duke, and then march everyone into the place while they hold on to the rope. Also like the Devon, it will be choked with office workers either on lunch or sneaking in for a cheeky pint before they head home, depending upon the time of day. As such, the high ceilings downstairs and the close proximity of everyone upstairs gives the place a uniform din that you have to combat when conversing. It's pretty daunting.