Excellent service! We came in 2 minutes after close but he didn't turn us away. Instead we were welcomed and served with a big smile! This has been the service we receive consistently, always very positive (all staff).
The last couple times we've been here we have been given very generous portions.
It's true what other reviewers have said about it not being authentic... But honestly hardly anything available that claims to be Mexican is (especially in this price range). Seems to be hardly a reason to give a bad review... This is Calgary...
Overall, I would say to go for the great atmosphere the staff create! And give that guy David a raise ;)