It's defintely a strong project with little volatility, I was just wondering if the fundamentals are solid.
Here are two more answers which are semi reassuring:
"I don't necessarily call this a flaw, it's just masternodes who are using third party software that can be compromised. If the data base is being hacked into you would hope that they would realize it and ramp up security for their users, it is how they make money anyway. I know that private send is going to be ramped up more in the future as well.
But to actually point out why this is basically impossible in the first place is that you need to somehow know an address is tied to a certain user and then hack into a data base hoping to find that users private send information. In the end you have just a normal transaction and really it's pretty hard to find someone off that alone. In the end it still adds security to the Dash network and creates loop holes that people need to jump through in order to trace the transaction. This article writer thinks that it compromises private send but it doesn't, it still has a use case. Instant send could have compromised the blockchain and was canceled before anything could happen."
"DASH PrivateSend can probably be broken by the US Govt if they devoted enough resources. They would need backdoor server access to thousands of masternodes located worldwide. That is possible for the US govt to do but probably not any other entity. And even then, the US Govt would have to dedicate a lot of resources to it. All it takes is one not compromised masternode to be part of the quorum and they wouldn't be able to track the tx.
Future upgrades to DASH will harden masternodes and make this type of attack impossible. It is already in the dev pipeline.
Also, it is worth noting that PrivateSend has never been provably broken."