I grew up in a Gulf-coastal state, where some Brahman influence is very helpful. In KY, it's not so necessary - and may actually have some negative economic impact, when those eared calves go through the sale barn. Brangus has its place, as do other Brahman-influenced breeds, but TX and KY are different. Would like to have a bit of 'ear' in my cattle, because of where I grew up, but I'm not willing to go there at present.
I used those red/yellow/spotted white-faced Simmentals back in the '80s, though CE/BW was always a principal selection criterion - even on mature cows, so I never had a problem with difficult calving. Still prefer that look - but economically, it's not for me here and now.
Yes, Simmentals today are black - and most are smaller than the average Angus cow or bull - thanks to progressive breeders selecting for better calving ease/BW, marbling, and other traits, far beyond just black hide color.
Despite their detractors, they're not just mongrelized Angus. Look at pedigrees - you may have to go 8-10 generations or farther back to find anything less than a PB or FB animal in most. Some Angus(and other 'closed' herdbook breeds) have 'suspect' animals closer up than that...
Went back to Angus bulls about 10 years ago; calves by the walking herdsire have been pretty decent. Most by the Angus AI sires we've used have been a disappointment. Have gone back to using some Simmental sires (black) - and the results have been pretty clear-cut, that most of the calves are better - and although they're black...they're not Angus.