I rode Steilacooms on my bike all spring, and I swapped them for Barlows once the ground dried. Steilacooms are fantastic tires, and very very fast for a knobby. They roll great on everything; they have enough tread for a little mud, but that tread doesn't seem to drag too badly on the road.
However, Barlows really are better on pavement. On pavement, the Steilacooms feel like they roll at 95% efficiency, where the Barlows feel like 99%.
The Steilacooms have an audibile "hum" on pavement from the tread, but Barlows have an audible "whoosh" noise when rolling. A tossup.
Both tires are about equally great on gravel.
I haven't flatted any of my Compass tires yet. So long as I don't ride in the street gutter (where the sharp debris collects), I don't have a lot of flats with any tire. But I'm not in goathead country. Both tires are tubeless-compatible, which is claimed to reduce flats in thorn country.
Eric-
In your situation, I'd recommend Barlows. The tread on Steilacooms is intended for muddy cyclocross courses, and it is overkill for dry roads.