At first, I wanna say that I'm pretty newbish to the thing.
So as Pinksomething pointed out, vendors can and will manipulate reddit and other websites with their fake reviews. This means even the really trusted vendors may be total scammers because all their reviews and comments about them are just themselves using different accounts. Then again, I could create a vendor account on, let's say, BMR, plus dozens of fake buyers account. I can buy stuff from myself and give a bunch of fake good reviews. I will probably lose some money because of transactions costs and shit, but who cares? Now I'm a trusted vendor and I'll send empty packages to people who actually want to buy from me, so the money will be released from escrow and I'm no more in loss but gain, and in the meantime I'll continue giving myself fake feedbacks and post fake reviews everywhere (reddit, BMR forums etc. ). So, how is escrow a solution? I really wonder how everybody still makes perfectly fine purchases and if there REALLY are any true vendors, then. Also, how can you trust groups like the LSD Avengers? Tell me if I got something wrong but anyways a solution is needed, and needs to be implemented soon. Someone should start a thread where each and everyone of us gives his 2 cent, and we discuss and upvote the best ones. I don't think we will ever be sure wether a vendor is scamming or not, but solutions that consider a lot of factors, reducing risks by a lot, are welcomed.
This is why you should never finalize early. If you order a box filled with weed, don't give the guy his money until you get a box filled with weed.
I never used BMR but on SilkRoad you could edit reviews after the fact. There's no reason why a vendor shouldn't have a record of bad transactions. Sure, they can still screw you, but so can a local dealer.