I think they have outgrown themselves.
The times I've had HDL back order things, they actually spent extra money getting me separate shipments, to the tune of spending $7 to ship 2 OIL FILTERS, in one instance. I'm not saying they're perfect by any means, and I'm only contrasting your experiences... They're certainly not the only place I order from, but they're pretty good. Chris' statement is salient.. how can you hold them accountable for a problem that could easily be the manufacturer?
If an item is on B/O, I think your order goes into a black hole. I ordered and cancelled my Cobra Speedsters 3 times over the course of 6 months before I actually got them. You usually do NOT get any communication from them once it goes on the B/O list. It just magically appears 3 months after you order it! All in all, I am pretty happy with them, I just wish they would communicate better.