This is kind of a pointless debate. The only reason Sust may look like it acts faster is cause of the test prop and test isocaproate esters doing their thing. Nothing at all to do with metabolism. Test is test is test.
id say that although sustanon kicks in quicker, because it has a little bit of test prop in it, sustanon is actually a far longer lasting drug because it contains several esters, one of which has a half life of over a month.
im not sure of the relationship between the various esters of test and the metabolism- if there is any correlation at all