I'll go in and kind of steal your thread here since there's no other answers yet and the title is already done. :D These are the criteria I would rate a vendor by:* Product Description: How accurate the description and image is of the product compared to what the customer is getting. For example someone ordering 2 grams of heroin ending up with 1.2 grams of heroin laced with 0.4 grams of caffeine is not a very accurate description. Bonus points for (truthful) lab analysis of any product.* Product Quality Versus Price: Is the price fair to the type of quality ordered? For example a product of bad quality which is extremely cheap could still rate high. Shipping Quality could to some extent be built into this criteria if it's exceptionally well done.* Swiftness: How quick the vendor is in dispatching your order into the mail system (without lying). A vendor which ships two days per week would not stand up to someone who ships every day.* Stealth: Using PGP for encrypted addresses is pretty much a given so I'll leave no further comment on that aspect. What it should primarily be about is the amount of work put into what's being sent in the mail to decrease the risks of customs intercepting it. This could be summed up in a few sub-levels:Stealth Level 1: No Stealth at all, the product is simply in the package without any padding/protection at all and can easily be smelled and sensed by touching the package. Might get through if there is no one inspecting the package.Stealth Level 2: The product is covered in something which hides the product from direct view if the package is opened by accident. Will possibly block some of the smell, sometimes enough for a human not to notice it but never enough for a dog on duty trained for that specific product.Stealth Level 3: The product is packaged in atleast one type of Moisture Barrier Bag. Will not be singled out by humans or dogs as there's no smell but will not withstand a direct inspection or x-ray.Stealth Level 4: The product is packaged in multiple layers of which one is a Moisture Barrier Bag. The product is hidden inside some kind of item which would be hard to disassemble. Bonus points for making the product look natural to the disguised object if it were to go through an inspection or x-ray.* Resolution: The ability to handle problems in terms of solving them and communicating this to the customer. For example if a vendor runs out of product unexpectedly he will quickly be able to inform the customer of the situation and try and resolve it as fast as possible. This criteria also includes answering questions in a timely manner customers might have in general about some product or such.* Trust: Basically if it's a well known seller with lot's of completed transactions. A seller with 500 completed transactions is almost always going to be favored over someone with 20 completed transactions if everything else is equal between them.If anyone have any suggestions on something I've missed or if you (don't) agree please post. :)