My existing countertop is in good shape, and is plain white possibly Corian or other solid surface. I'm not planning to replace it, but am replacing the sink and faucet.

The current cutout is rectangular, and I'm interested in dropping in a Blanco Silgranit Diamond Super Single Bowl. The cutting template I see calls for curved sides and radiused corners.

I have not taken precise measurements of my cutout, but I'm wondering if, assuming it's large enough, I can drop the sink in to a rectangular hole, or would it feel too loose?

If the hole I have is already slightly larger than the template calls for, do I have any options to make it work? If it's slightly smaller than the template calls for, how difficult is it to cut Corian?

Thanks!