We have four farmhouse style sinks in two different houses, and all present the same problem. It doesn't have anything to do with the material as two sinks are concrete, one stainless steel, and one composite stone. With the two kitchen sinks it's very frustrating spraying out the food particles from corner to corner. Food particles go from one side to the other, and it's very difficult to corral them to the drain. The two concrete bathroom sinks don't have enough slope, so when shaving and brushing teeth, the water and material flow to the opposite side of the sink. It's annoying to wash a 3' wide sink every time it's used. And gross if the sink isn't cleaned from side to side after every use. As a compromise, we're installing a farmhouse concrete bathroom sink with two drains and more slope. As I evaluate many things in life, a, farmhouse sink is a solutions looking for problem.

Hmm, 200mm diameter is about the size of a side plate, 300mm dinner plate and after a quick look at a few sink brands (eg Clark they seem to all be closer to 400mm). I did comea Cross this one but have no idea of the brand quality http://www.swanstreet.com.au/CM1-Undermount-Single-Bowl-6L-Small-Bar-Sink-330-x-200-x-125mm~3600

If behind doors, I would be looking at my budget and deciding from that.

My sister had a lovely round ceramic trough/basin