EM did a comparison of the 270 to the 240, on a 440. The 270s were better everywhere, including low end torque.
If you're willing to confine yourself to maxwedge port intakes, I'd run the 270s. As head limited as a 440 is, I'd go for the biggest and best heads I could afford. (Just decent aftermarket bbc heads outflow 270s by a pretty good margin. A small oval port is 290cc's, and outflows the 270 by almost 50, and 320 and 360 cc heads are everywhere)
And for a badass street motor with a bigass cam..... solid roller, 100%.
And I'm not a gambler. I'd set the c.r. at 10.5.
Give up 10 or 20 hp for a better chance of running on straight pump gas? In a street car? Yep, I'd do that.