I've been buying drugs online since 2001, back then it was PayPal or bank transfer.
Out of hundreds and hundreds of deals over the years, I have only been burned 3 times, each of those 3 happened in the last few years with the rise of dark net markets, each time due to a market exit scam.
I would much prefer a market whereby they held no escrow nor handled any money whereby I would pay a vendor directly, yet still retain the features of a centralised market with reviews etc...
Of course, vendors can run exit scams but they affect a much smaller proportion of users and generally speaking vendors with a good history are less likely to want to destroy their business and more likely to want to keep operating to make more money in the long run.
As a buyer, you should spread your risk across multiple vendors. Don't just pick the number 1 guy and spend all your coins, spread it around, find out who's good and remember if you do get scammed by a shit vendor that it's better than everyone getting scammed.
It is interesting watching these exit scams. In the research chemical community, almost all deals are direct using non-refundable payment methods, but they appear (from my standpoint) to have fewer problems with scamming than the DNMs, because as soon as a vendor starts screwing up, word spreads like wildfire and orders stop.
Then again, there are probably a ton of neophytes getting scammed. Just don't hear about them, because the person isn't active on the popular subreddits and forums.