Thanks Dun.
Yes, the latest MARC info says that Simmental sires now calve easier than Herefords, and comparable to Angus (within 2%) when used on cows.
This is a pretty blanket statement and refers to breeding cows, but sires with a +10 CE are recommended for all heifers - including all British breed heifers.
SimAngus is getting extremely popular - using Angus on Simm cows AND using Simm on Angus cow. I would venture to guess that there are more ANGUS cows being bred to Simm bulls than the other way around. Big PB Angus farms having been using Sim bulls for quite a while now.
Interest in my Macho bull started out with PB Angus breeders wanting semen.
There are bulls of all breeds that are "cow killers", but you will find a lot fewer in the Simm breed - especially comparing to other Continental breeds. In this day and age of EPD's, very few males with poor CE & BW EPD's get sold as a breeder.