Although this location does take walk-ins, it would behoove you to make an appointment if you would rather not spend an afternoon waiting. Lots of Sun City Westers come here so expect a wait if you didn't make an appointment.
The staff is nice. The front desk guy is a bit indifferent but I imagine I would be similar in stature if I had to deal with the elderly all day long. Not to say they don't deserve to be treated well, but I've seen them in action and they can be tiresome at best.
The phlebotomists are very proficient. My blood is not easy to draw yet they never have a problem. They are kind, professional, and make the process not so bad.
So what did we learn? Make an appointment, be patient with the oldsters, and the process isn't all that bad at this location! :)