Depends on what you want to specialize in. Accenture is better for IT consulting. Big 4 is better for finance/audit. If you want to exit to finance, Big 4 is better. Pay wise, Accenture pays more at the start, but Big 4 equity partners get paid very well (>$500k per year), though it depends how much you sell.

I think on balance of probabilities, Big 4 is still more "prestigious".