We were purebred Black Angus for 3 generations. I tried some Gelbviehs and others, but ended up with Galloway bulls on the Angus cows. Wanted a little more hair and hardiness for Canadian winters, and we were working towards grass finishing our beef. Galloways have their chassis a bit lower to the ground, with more flesh than flash, so we've found they grass finish easier than any of our Angus did. They're tough, hardy, and pretty hands off. They work for us, that's what counts.
If we expand in the future with any crosses it will be Highland-Angus-Galloway crosses. Angus for more carcass, Galloway for grass finishing ability, and Highland in the cow side because they're the most instinctual mothers I've ever had, and they're tough as fender leather.
Overall, I'll say that I've seen great cattle in every breed. If you gave me a herd of purebred Limousin for 10 years they'd be adapted to our ranch and management and work well in the long run. And in 3 years of brand inspecting I was chased over auction market alleyways by every damn breed known to man, so no one can tell me that one breed is quieter than another. Disposition is a result of management and environment over generations.