My understanding is that the Tech Review SENS challenge has not produced any plausible critiques of SENS, therefore I suggest the bets are raised! Raise the challenge to maybe 50000-100000$. Could Metuselah foundation and Tech Review work a deal on this?
SENS would get great round of publicity pointing that no one has answered the challenge and anyway, the sooner we find something wrong with it the better. If still no one finds anything wrong with it, that would be an EXTREMELY good leverage for the implementation of SENS.