I'm in a position to answer this.....literally.

I'm sitting at my island which is a little over 10' long. Next to me is a drawer with a measuring tape, so I got it out. I have a 33 on the side, at the end. It will be fine. Don't forget, if you put the cutting board in, then there is only an 18" hole.

I have my sink in a custom cabinet, which I had designed so that under the drain board side I could have a knife drawer, with a double trash can pullout below it. The knife drawer is a little shallower to be able to fit in under the drain board part.

Try to keep your faucet, soap, airswitches, etc to the left of center. This allows you to access the sink from the short side and the long side. I use that more than I thought I would.

Beekeeperswife,
What do you have under the right side (deeper basin) of the sink?

It's a cabinet with a door. (Sort of a traditional sink cabinet) And a tilt out drawer thingy.