I posted a while back about my most recent positive experience with DGC -- an item I had ordered was not available when they went to pack the order, so they called me with a list of potentially acceptable alternatives (same mold, closest weights/colors in stock). They could've just e-mailed me, or they could've just called and put the onus on me to figure out what they had that would work, but they did the legwork before calling me so that all I had to do was say "yeah, that'll work".
Haven't had a lot of other "customer service" interactions with them -- my other orders have pretty much all been shipped/delivered as ordered with no delays or errors.