Earliest-maturing heifers here, have been, year-in/year-out, Simmental-sired - often in heat by 6-7 months of age. 0
Have had a hard time getting high% Angus heifers to cycle by 15-16 months.
First Braunvieh-cross heifers in our herd are just now 14 months... have not seen them in heat yet... but we've made the decision to hold ALL our heifers 'til they're around 18 months to begin breeding... gives them a tick more frame, and seems like fewer of them have difficulty breeding back while raising their first calf.
Have no recent experience with Salers; in the past, bad temperament was an issue. Breeders may have addressed that issue... I dunno.
Depending on where you're located, the Brahman influence from the Beefmaster deal may or may not be a positive. I've seen some BMxAN heifers at select heifer sales here in KY... and they looked fabulous... I doubt the 1/4 Brahman blood would have any negative repercussions, and bred to non-Brahman terminal bulls, I'll bet their calves will mash the scales.