The first delivery didn't go well. The account information provided was inactive. Their customer service nearly INSTANTLY gave me credit back for my purchase and asked me to place the order again.
The second order was delivered very quickly (<15 minutes) but was missing an item. At this point, I didn't really feel like fussing around with placing another order or getting a refund, but I did want to let them know.
They were more than understanding and on my side without a shred of doubt. They again gave me credit for the item that was not delivered and requested I place the order again.
While the opening experience of the delivery was pretty discouraging, their customer service more than made up for it. Had these been more expensive items (my total was like 15 bucks) I may have been a little more upset. But ultimately, they aren't the ones who are delivering the items. It's their affiliates who are not d2mule employees, but rather just 'suppliers' of the requested items.
I'll order again from them.