Doin' it the other way around here - Shorthorn bulls on high-percentage Angus cows. The SH-sired steers are blowing the doors off anything Angus-sired; stacking up well against Simmental-sired calves out of percentage Simmental cows(though almost all of my SM calves for the past 3 years have been heifers). Keeping most of those SHxAN heifers to breed to Simmental sires.
Yeah, I'm getting some red calves here and there...but Angus-sired calves here for the past 8-9 years have been mediocre to average, at best. We've got no plans to go back to Angus sires any time soon...If I need black, I'll use black Simmental bulls.