Medium sized undermount kitchen sink

Need to get more specific than "medium sized." What dimensions?

I recently needed a 21" sink and found this: http://www.amazon.com/Elkay-EFRU191610-Avado-Undermount-Stainless/dp/B0019GJ8G6

21" - 24" is my preferred size.

I've had one of these black granite sinks for about 4 years and they look good, don't get scratched, and never show dirt. They're fantastic.

http://www.ajmadison.com/cgi-bin/ajmadison/441367X.html If you can find a deeper one, you can hide more dishes in it.

Franke is another brand that I have seen in quite a few good apartments, and thay make durable sinks in the size range you're looking for. Many have good depths if you have the clearance for it (completely agree with needsadvice above).

Very happy with the Blanco Precision unit I've got.