As far as I know, current clinical evidence shows that modern porcine insulin isn't actually any better or worse than synthetic human insulin overall. However,

As far as I know, current clinical evidence shows that modern porcine insulin isn't actually any better or worse than synthetic human insulin overall. However, it's also not any cheaper these days either - in fact, I think the NHS pays slightly more for it than human insulin. Sure, managing to program bacteria to produce complex human biomolecules was a major breakthrough, but the tech is old and refined enough that companies can churn the stuff out relatively cheaply.