Different eras, different times and judging standards.
Jays legs are what the current people want (minus the asymmetry), but Arnold had the ideal overall look.
But to play devils advocate and play along, I'll sum up my views as below....
How many victories does each have? Arnold has 7, Jay 3. Based on that alone Jay would be #2 between the two.
Stemming from the above question, how many victories did each deserve? Arnold deserved nearly all of his- with only 1980 being controversial. This is not the place to argue the Arnold/Metzner debate, however. Nor is it to say that Arnold should not have won in 1972 over Sergio. Jay definitely did NOT deserve his second victory, and he lost the title one year between his 2nd & 3rd wins. Arnold did not do this- only retired and came back and still won.
So, leaving it brief, I'll say that Arnold is numero uno and always will be.