For what it's worth ... secure multiparty computation requires a trusted setup.
Unless I'm a party in the multiparty (or you are, too), why anyone would trust a trusted setup is beyond me. Note that there is no indication that the secure multiparty computation was compromised and currently there is no auditing mechanism to find out!
Ring signatures, on the other hand, suffer from sybil attacks in that a malicious actor could try to make available his public keys to be included in the signature.
That said ... just because people (speculators) don't understand the intricacies of a particular technology, i.e. the mathematics, doesn't always imply that the token is not a good investment vehicle.
Finding out in detail how much a dev understands this technical background is always a good start.
Then again ... I tend to invest tokens based on utility, application, and, foremost, technical prowess and innovation.
ZCoin is most definitely on the list.
yes, speculators like myself mostly go by utility than technical prowess, and while it may take some advanced technical prowess to effectively provide privacy on blockchain, the utility of privacy is not worth anything speculatively because of so many coins who claim to have or will have privacy, steem included https://steem.io/roadmap/confidential/
You may be right, except ONLY those that have been proven to have the best rock-solid privacy will become the ones that rich people with $Millions will store their money. For example if you have money you wish o hide from your wife because of divorce laws in your country, you will not risk that by using a coin that "claims to have" privacy or has weak privacy and/or security (for example Dashcoin). For the majority of saving accounts which will not have much money, yeah, most people will not care and good-enough privacy is OK. So there will be different coins with different use-cases. Both may gain sizeable market cap but for different reasons - different users and use cases.