I don't know about other Nickel's restaurants (for example there is one Ste. Catherine street) but this one on Cote-des-Neiges is pretty ordinary. The diner decor at times looks a bit dirty, the food is bland and the prices are not that low. You could have more value for money or simply more better quality food at one of the many breakfast serving establishments in th CdN neighborhood.
I won't return or recommend it to my friends simply because their food and service are pretty ordinary and that better options are not far off .