What about the CryptoNote ring signature tech that's been verified by cryptographers?
I wasn't aware of it being broken, do you have a link?
Im looking more into this. Does XC implement this tech?
This tech actually seems pretty promising, and I see many coins (with lower caps than XC) use it.
I have to work it out in my head... not sure how the system holds against someone analyzing the input and output amounts of a a transaction.. but I will get to the bottom of it.