Former Host of SCP13 here.
Cobraman has worked with me on the SCP13 project for several months (the exact dates are unknown to me at this time) and has shown he can adhere to rules and act in a mature manner. Obviously, I cannot comment to his behavior here, SCP13 and CM were - while it was alive - on two different ends of the spectrum, but I feel that if I had to take what's been said so far into account and put that next to his behavior in the past months in SCP13, he has matured a great deal.
That's as far as my vouch goes.