Exchanged some $ here the other day. They responded one email relatively quickly, then nothing, and I had to call a few times.
The store is actually almost like a bank. The exchange rate I got was pretty good, I paid using Interac, which was straightforward. They weren't exactly very friendly, however I got what I needed.
They do offer free 30 mins parking, but you have to go into the underground lot, which is quite cramped. They will give you a card to insert before you insert your parking ticket at the exit.