Could you post me links to the evidence if you don't mind? I would like to read this to get a more unbiased opinion. Thanks
Version 0.2 was demonstrated to be completely broken:
A perpetual tournament is proposed, in which stake holders try to compete against each other for generating the longest consecutive fork. This will provide an empirical means to investigate the security of the ppcoin network and show strengths and weaknesses of the current scheme.
I've shown before that I can generate large consecutive chains of blocks by just bring the exchange cold wallet online. The first time I did this I got 84 consecutive blocks. The second time over 100. Yesterday I brought another wallet online and left it running. When I closed it overnight it had 400 blocks in 'immature' status. That is probably why POS difficulty is currently 30+. The exchange doesn't have that many coins. There are people out there with more coins than the exchange I'm sure.
(Proof-of-stake's only purpose is to make generating many blocks in a row hard so that double-spending is hard. If it is easy to generate many such blocks then PoS doesn't work as advertised, it is a sham.)
I do not have such data about version 0.3 (I completely lost interest), but Jutarul claims that it has same flaws as previous version:
https://bitcointalksearch.org/topic/m.1952272And I have all reasons to trust him, since he previously demonstrated good analysis of ppcoin security, Sunny King even mentioned him in version 0.3 announcement:
The protocol upgrade in 0.3.0 includes a new algorithm to derive proof-of-stake hash modifier, the entity that scrambles computation for stake owners, ... Honorary mention also goes to Jutarul, who independently discovered and verified an issue with using difficulty as modifier and published on bitcointalk in December last year, while successfully executed a demo attack on the block chain.
Then you have a hilarious statement from Sunny King that he has no idea how secure PPCoin is:
You are right I don't have a math analysis of how much coins are needed to attempt control of block chain.
But the problem is that Sunny doesn't want to help people to research this independently, he offers no documentation and says people should just read source code.
So, the summary is that PPCoin is a thinly veiled sham. Situation might change only if Sunny will be willing to help researchers to analyze it.