It's got Steiner, Online Authetics, and PSA/DNA, so unless it's an elaborate scam, it is good. The Sandy looks okay to me, but the Koufax sure looks funky. Likely okay, just atypical.
I would not want it. Not because I think its fake, but because it's an ugly example. Why pick the dented can when there are plenty of undented cans on the shelf?
Online Authentics doesn't actually authenticate as far as I know anymore. Muhammad Ali uses them for his signings and I imagine a few others do, but read their website to find out the limits of their certifications.