This location is nice and clean. It is really busy in the mornings, so unless you are fasting and want to get your blood drawn ASAP, come in during the afternoon hours.
I made an appointment online for 4:30 PM for a Tuesday the day before via the internet. I arrived exactly at 4:30 PM and got called up at 4:32 PM. There was only about 5 other people there. I was walked out at exactly 4:40 PM with everything done!
I doubt this will happen to you EVERY TIME, but from this situation, I've learned to always make an appointment. It will save you time in the long run.