I waited over 4 hours (I was there at 9 am and didn't get in the rooms til 12 pm but saw the lady doctor at 1 pm) to see the doctor. The wait time is perhaps longer here than at Markham-Stouffville's emergency hospital.
I would not recommend this place at all. Although the doctors there are experienced, this office has been around since the early 90's where they used to have scary clowns in the ceiling, the wait time is not worth it. It's a large office with lots of seating but even then, there won't be enough seats, as many patients come with their parents or significant other.
I had to go to her because the other walk-in clinics I went to which were recently opened walk-in clinics, I found the doctors to be inexperienced. My family doctor was away on holiday so I had no choice but to visit a walk-in clinic.
Now I take extra precaution to avoid getting ill because the health care system in Ontario has completely failed us from a patient's perspective.
* 1-Week Later (for a doctor's note) *
A side note, I was in the waiting room area and a couple had an appointment at 5:30 pm. They showed up at 5 pm because they knew of the long waits. They didn't get into the small rooms until 7:30 pm. I heard the doctor speaking to them and that was around 8:00 pm. I finally met the male doctor to ask for a doctor's note (gave him $20 cash on the spot, I guess I'm paying for his dinner tonight...) and it took less than 5-mins.
Overall, I'd personally stay away from this walk-in clinic and just go to the hospital if you need to see a doctor and your family doctor is away. At least in the hospital, you're guaranteed to get pre-screened by a nurse to determine your severity and pray that the day you visit the hospital, there isn't a car crash in the area.