I have dealt with these guys many times and let me just say that it is Always a pleasure.
My latest experience was no different. Due to an out of stock item we were e-mailing back and fourth for a little more than a week. It was a body pin for a 416. Since he couldn't get one fast enough from his distributor he contacted Umarex directly and had them send one out. I received my order last night and the pin didn't quite fit. So I shot an e-mail out to them saying that I received the order and I was happy with it but I told him it didn't fit. I, almost instantly, got a response to where he told me that he was sorry for the inconvenience and that he would refund me for the part and I could just keep it. I told him it really wasn't necessary and that I would just eat the cost (it was $5). He said he was happy to do it and went ahead and did it anyways.
I can't say enough how constantly awesome these guys are. Not to mention that they are out of PA so it's always super fast shipping.