Our rig has a single deep square/rectangular tub with a flat bottom, a useful size sink. We manage quite well washing dishes by rinsing everything first, then using the largest pot or bowl for the soapy water. Since we exclusively boon dock, we wouldn't fill a sink up anyway, just to conserve on-board water.
Those round/oval sinks appear to be quite difficult for general kitchen utilization. I would change it if proven so.
Here is our single bowl square/rectangular deep bowl sink. It really does work quite nicely. Phoenix Cruiser owners never have anything bad to say about it. The stove and sink both have matching Corian covers. You can see the stove-top cover in place. They store in a pocket behind the stove.
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