I'd be most interested in like-for-like (to the extent possible) so wide and narrow in the same model (23 and 32, or 28 and 40, or whatever). Rubino Pros are crummy OEM tires, and butyl tubes are markedly worse than tubeless. And part of the total package is that you can use (and get benefit out of) aero wheels with narrower tires than 37WAM, but Aksiums mask that.
That said, it's not like I think the results would be drastically different. Is ST still filled with a "narrow is aero" crowd?