The MSR Titanium kettle is a 850 ml mug with a sturdy handle and a flat lid. I’m not sure why it’s called a kettle since it’s more a mug/pot. It can be used for 1 person as a universal pot/mug or for 2 people if you don’t plan on cooking something complicated like lasagne. It works just fine for 2 portions of cous cous and similar instant meals.
Primus is a Swedish company established in 1892. That’s surely enough time to figure their shit out. And they have. Their stoves are legendary. Some people even refer to any backpacking stove as a “primus”.