Hughes STL5460AS-8 vs Lunati 40200913LUN cam

I'd agree, the three degrees exhaust duration won't mean much, but the rollers area under the curve will. The roller should have more duration at .200, .300 .400 lift, and make more power as a result
Engine masters did a similar test on a stout Steve Dulcich built 408 Mopar, and the roller made about 25hp more on the top end than a very similar flat tappet. Still something of an apples/oranges test.