I was attending a two-night run of concerts at the Air Canada Centre and could not be happier about my stay there. Took the train from YYZ airport to downtown, walked about three blocks, and was at the condo. For my whole trip, I did not need to rent a car or hail a cab. Everything I wanted was either across the street or two to three blocks away.
Across the street is a really nice upscale grocery store with an amazing deli selection of freshly prepared meals, sandwiches, and snacks. This was particularly inviting if you're looking to save a little bit of money on meals compared to eating out at the downtown restaurants (which can be a little pricey for standard pub food).
The condo itself was new, nice, and clean. While it has only one bedroom, it could accommodate one other guest on the couch, but I probably wouldn't have more than three people there unless you're comfortable sleeping on the floor. Remember, this is a condo, so there are not any extra amenities like a roll-away bed, no cribs, no housekeeping, room service, or anything like one gets in a hotel.
I will definitely look into TO Stays in the future if/when I do another event at the ACC or Rogers.