Hi Mabies,
We have a 30" base cabinet and a Julien 28" x 16" x 8" undermount sink. The corners are 18mm which is a beautiful radius--easy to clean, but still clean and contemporary looking. It is mounted directly to the soapstone counter without clips. One side actually rests right on the edge of the cabinet, because we have it just slightly off-center to better align it to the window. We are very pleased with our choice. I know many people love a deep sink, but after accounting for the countertop, our 8" sink was over 9" deep and it became uncomfortable to reach to the bottom. We purchased the Julien sink grid after the fact, which helps a little.

Here is a link that might be useful: Julien J-18 series

With a "D" sink, you often get more depth (front-to-back) than with a traditional rectangular sink. Yes, if you have standard depth counters you probably will have to mount the faucet off to the side (on the curve, probably). However, this has two advantages (speaking of "D" shapes in general):

(1) Gives you a larger volume sink compared to a traditional rectangular sink of the same width

(2) Brings the faucet closer to you so you don't have to reach as far to get to it...especially helpful if you are short or have short arms.

I would keep looking until you find a sink you like in your preferred composition and color. BTW...the exterior dimensions are useful for determining whether the sink will fit in your sink base (recommended 1" or more less than the width of your sink base). The internal dimensions tell you how much sink workspace/volume it has.

As Sandn mentioned, keep in mind that the final working depth (top-to-bottom) of an undermount sink is equal to the depth of the sink + the thickness of your countertop.