For such a large store I'm always impressed that any time I ask any employee where something is they can always tell me what aisle its in and sometimes even where on the shelf it will be.
I like the surplus section. Its always changing and will have things that you wouldn't normally find at an auto parts store.
I haven't done any direct price comparisons as I'm usually looking for something specific that other stores may not carry, but they seem to be very competitive on most items.