The large bowl fits all my pots & pans, including handles, as well as my longest cookie sheet, refrigerator shelves & bins, and Vent-A-Hood insert (I hand wash it). I can also fit several mixing bowls along with miscellaneous other items in the large bowl at one time.

The small bowl is perfect for filling pots (all but my 12qt pot fit in the sink)...with a pull-down, I find pot filling works best when the pot is in the sink (there's no "hook" to the faucet head to hook it on the pot like my pullout has). It's also small enough that if I want to soak utensils, etc. I can do so without wasting water or having to find space for a dishpan.

As to using tubs & accessories to mimic a double-bowl - you have to find room to store all those things when they are not in use...I know I don't have extra storage space for that!

If you do not have a prep sink, I think a double-bowl sink is more useful than a single...if it's big enough. Personally, I recommend a 36" sink base for a double-bowl and a single-bowl for anything less than 33" wide. 33" is iffy - you could go either way.

I think if your larger bowl is at least 20" wide, you will be OK.

Overall Dimensions:
35-1/8" x 20-7/8"
Interior of Large Bowl: 21-3/8" x 18-3/4" x 9"
Interior of Small Bowl: 10-1/2" x 15-7/8" x 7"

Large bowl at work (21.5" wide):

Small bowl at work (10.5" wide):

Some other threads:

http://ths.gardenweb.com/forums/load/kitchbath/msg0115411824187.html
http://ths.gardenweb.com/forums/load/kitchbath/msg0717064115325.html
http://ths.gardenweb.com/forums/load/kitchbath/msg0514051915205.html
http://ths.gardenweb.com/forums/load/kitchbath/msg0519354019922.html
http://ths.gardenweb.com/forums/load/kitchbath/msg101814182982.html

I ran into the same issues that joaniepoanie did with regards to runnels in granite. Instead my fabricator was able to do the sloped drainboard, and we love it!