Wen I had two sinks, I had a disposal in each, and used both frequently (we compost more now so we hardly use the disposal at all anymore, but we still have one for odds and ends).

Not one or the other. Both. One of the best pieces of advice my former GC gave me was to put GD at both. We compost a lot, but I'd hate to be digging out grimy food bits from either sink. Prep sink has prep bits. Cleanup sink has cleanup bits.

Both. :)

Edited to fix typos from ipad auto-text.

This post was edited by breezygirl on Fri, Sep 6, 13 at 16:43

Do you have one now? You could put tape on the switch to stop using it for a week, then you would know. I spent a week on vacation in a house without one, and decided to put one at each sink. Costco had a good deal.

Wow! That was pretty unanimous. I have one now which is why I want one (but we only have one sink). And yes, I run it for 10 sec almost each day. I don't throw huge chunks of food out, it's just the loose bits and pieces from rinsing veggies or what remains on the plate when I rinse before putting it in the DW (yes, I know that's a no no) Ugh, it's another thing I am adding which I guess the contractor will consider a change order (blech)

I might have filtered water at the prep sink. Do you think it will get too crowded down there? I talked to one water guy who was recommending a $600 system (plus cartridges) to filter the water from chlorine, bacteria and parasites. I think the main system was to go under the floor (not in the cabinet) but I know some filters go under the cabinet. DH thought the $600 system and the cost of the cartridges at $120 per 6-9 months was high compared to some GE models but I don't know if they were filtering out the same things.

The man recommended putting the filtered water faucet on the main island in case I have to fill a large pot for soup but I only make soup once or twice a year and I measure out the water in the measuring cup. I think it much more likely that someone would want a refill on the island and might be able to reach across to the prep sink to get it. Also, I was thinking I could put a large pitcher in the prep sink and use that to fill bigger vessels for say, lemonade, for a large party

But I digress. OK, will add another one (perhaps just a low end model) to the preps sink.

Thanks!

CT, I included info about filtration in responding to one of your other sink threads http://ths.gardenweb.com/forums/load/kitchbath/msg090011365693.html
To really decide on filtration, you need to know what is in your water that you want out - and how much flow you need. There are many threads on the subject in this forum, appliances, and plumbing.
Fitting everything under the cabinet is one thing, wanting a lot of holes in your countertop and hardware on your island is another thing.

We are doing both.