I've just read through this entire thread and I'm still a bit puzzled as to what the consensus is...
What I have learnt is that bitcoins and the silkroad are not 100% infallible, but how would it compare to real life transactions? Purchasing may be ok for personal use, but what if you have a desire to supply? A system like this would probably cut out most if not all the risky contacts you'd normally have; people who could very easily turn you in to lessen their own sentence.
A bit coin system and buyers on SR would allow you to receive funds, then package securely what you have produced before it gets sent to the rightful purchaser, all in a few steps. If you managed to keep your operation quiet and only sold to SR buyers, it would be very difficult for you to get tracked down, would it not? IP trace isn't very accurate, so I suppose that would just leave the bitcoin transactions that would be risky?
If you didn't have any safe people or didn't want to have to trust anyone in selling your wares, would this not be the better alternative?