A metal mount is generally superior to a plastic mount as it is more durable.
A longer maximum focal length allows you to focus in on a small part of a scene, and offers a narrower angle of view than shorter focal lengths.
We consider a lower weight better because lighter devices are more comfortable to carry. A lower weight is also an advantage for home appliances, as it makes transportation easier, and for many other types of products.
The front element doesn’t rotate. This is important if you use filters, as some such as polarising or gradient filters have to be orientated a certain way.
A shorter minimum focal length allows you to get more of the scene in the photo, and offers a wider angle of view than longer focal lengths.
The device is protected with extra seals to prevent failures caused by dust, raindrops, and water splashes.