Pro Lab Choices

I am expanding my business next month and I am in need of a good lab.

The lab I use now is through SmugMug. I will be adding services not available through them.

I sampled WHCC, BAY Lab, and Millers. They all had fine prints which had only minute green variances between them ( non-lab adj. ).

The only important difference was that Millers shipped in strong cardboard (great) while the other two shipped in thin card stock which I fear will cause damage in shipping one day. WHCC had small dings in all my prints. The envelope was undamaged so I suspect it was damaged at the lab.
What are your choices for labs and why.
Thank you for your help,
Ken