My understanding is that PoS has attack vectors that are not present in PoW, giving the attacker a cheaper way to totally control/destroy the network.
Can you elaborate? I have observed exchange price action and noticed that when 1% of NXT is purchased at market price, this drives the price up 25%.
As I pointed out in the other bitcointalk thread, my basic NXT PoS soundness questions raised in
https://nxtforum.org/general/forging-questions/remain unanswered.
So one attack vector is forging with timestamps artifiically advanced by almost 15 secs,
and having many nodes disagree on whether the new block is valid or not...