Almost all have appeared in tiny speedos or revealing briefs on Australian soaps or films.
In terms of bulges McMahon, McPherson and Worthington were all unimpressive and average at best.
Hemsworth and Spencer boast a bit more bulge action but again nothing to write home about. Both are probably average to just above average.
Russell Crowe - All the reports I heard said he was average, but he's got a decent sausage on him if you see the scene in "Proof" where he's hastily getting dressed and has to tuck his briefs-covered cock back into his jeans.
Eric Bana - There are no nude shots, only caps of him whipping out a prosthetic penis in "Chopper" or flashing his bum. Much more telling was his work on the sketch comedy series "Full Frontal" where he appeared in speedos and leotards. Dick appeared average length (and slightly above average thickness), but his balls were huge.
Crowe is confirmed uncut. Hemsworth, Bana and Worthington are almost certainly uncut. McMahon is more likely cut due to his age. No idea about McPherson or Spencer.
As for the additionals brought up - Alex O'Loughlin is well hung and likely uncut. Andrew Lincoln is British (Crowe is NZ-born, Worthington is UK-born).