If mini zebu are anything like their larger cousins the regular ole brahma cow, I'd say go find a gentler breed! My experience is mostly in regular beef cattle, not minis but here's what I know: Brahma are popular here because they sweat so they're cross bred on the beefier breeds. The do much better in warmer weather. They have thick hides that aren't as susceptible to mosquitoes and bugs, Nearly every cow around here has some brahma in it, but the smart peeps keep as little as necessary (like a 1/4th or 3/8ths I forget exactly how much is needed to still be useful.) Entire breeds were created trying to find the perfect amount of sweat/hide without the brahma attitude. Brahma are know to be a bit wild, they're unpredictable, hate being in a corner, making them hard to pen and work and will jump fences like a deer or just plow through the fence, they don't much care one way or the other. They can be fast and aggressive and generally hard to handle.
I'd love to have lowline or mini herefords but whew...have you priced them? ouch. So I'll probably end up with dexters instead. Regular Hereford cattle are my favorite, they're so laid back and calm if the smaller version is the same in personality that's what I'd go with. My grandpa used to keep a herd of brahma and he had a hereford bull that I LOVED. Then he got tired of fixing fences so he switched to braford cows with a brahma bull and eventually switching over to nearly all Beefmaster. Beefmaster are nice for small ranching, nice and hardy. I kept beefmaster for a little while, til it got to hard to keep up with everything while we lived in the city. I'm probably going to keep a very small herd of something small. Dexters probably, but I'd never choose pure brahma ever! Dang brahma...I am not fond of them at all.