Like @djashones, I also use mostly Fibaro and Aeotec dimmers or switches. If you want them installed in your switch boxes without neutral, you need the dimmers. If you can get them into the ceiling or ceiling rose to access neutral, you can go for switches. I'd actually recommend installing the dimmers, even if you might not have dimmable bulbs installed. The dimmers can be configured to act as on/off switches, but if you decided to switch to dimmable bulbs in the future, you can also do so without have to re-install anything. Two disadvantage to the dimmers, though: 1. Lower power rating and 2. Only available in single options (I think) whereas you can get the switches in double options
I really like the functionality of these devices, and I wish I could find Zigbee equivalents, but so far I haven't found any. At least none that are certified for Australia. So, in my house, I've ended up with Z-Wave pretty much throughout for dimmers/switches, and then Zigbee for sensors and smart plugs. I definitely recommend Zigbee for motion sensors, and I think most people agree that they seem to respond faster than the Z-Wave options (although the newest Z-Wave devices are supposedly better).
As a couple others mentioned, it's probably worth going for the trusted brands, especially for mains-powered devices that will be living inside your switch boxes or ceiling space. I'm not familiar with the Zemismart products, but they look to me like fairly cheap, rebranded devices. As tempting as it is to go for the budget options, there are some things I'd rather spend extra money on.