SC,
Have had several CO calves here, out of 2-5 y.o. ANxSimAngus cows - no problems. Have not used any SH bulls except Waukaru Goldmine 2109 on virgin heifers, so far - and they get here OK.
It's not always the bull's fault - the cow contributes half the genetics. First calf crop from the current Angus herdsire here started out with what was likely a 50-60 lb heifer and culminated with a 105# dead bull I pulled from a 4 y.o. SM-cross cow with some Charolais back behind her a ways... she gave us a 107# SH bull this spring.
Commercial outfit here, we don't routinely take BWs - unless it's a big DEAD calf - though we participated in a progeny test breeding trial for a SH breeder this year and had to collect BWs. Some were by a bull we've used in the past - wouldn't use him on heifers, but have never had, nor anticipated, issues on cows. No calving difficulties, other than one that had an elbow hung on the pelvic rim - and he was an easy hand-pull after we got that corrected. But, due to the much colder-than-usual winter, and increased amount of DDG we fed to make up for poor hay quality, calves were considerably bigger than we've been accustomed to. BWs ran from (excluding a set of twins - 69#heifer & 94#bull) 85# to 107#. Avg BW for the two bulls tested ran ~ 96.5#.