I went here a lot to purchase supplies for a summer school drawing class, and to get mats for a photography class. They have a full range of pencil brands and hardnesses, and a decent selection of papers.
I thought the mats were a little on the expensive side-especially the acid free ones which were about $15 for a 32" x 40" sheet.
As for the staff, it was really hit or miss. Sometimes I would get someone who knew exactly where an item was and would actually walk over to help me get it. Other times, you would have thought I was asking the counter clerk a differential calculus question instead of "hey, got any 9b pencils?"