I have searched and read a lot of comments about second dishwashers. It seems a lot of opinions that it is best to have both together flanking one sink and alternate use. However, the only reason I am thinking of a second dishwasher is my clean up sink will be on the front wall and the prep area is the back side of an island (looking front, with ovens and cooktop on the back wall). I am thinking if I had a second dishwasher next to the prep sink on the back of the island the prep and cooking items could go into that dishwasher and never have to come forward to be washed and then brought back. I'm thinking measuring cups and spoons, bowls, colanders, cutting boards, stirring spoons, spatulas, whisks, etc. I currently tend to hand wash bulky prep stuff like salad spinners, colanders, large mixing bowls unless I happen to have a very empty dishwasher. I'd think with this setup I'd use the dishwasher more for those items which would be a bonus. The clean up sink would handle the dishes from meals, serving, glass storage containers etc and the washing of large pans that are hand washed.
I wouldn't do two dishwashers by the cleanup sink as my main motivation is to load/unload all the items used in prep closer to where they are used. It would also help me cook and clean as I go better.
I know I might end up doing more loads this way as I could have two partially filled dishwashers but I think the prep one would get run more (as I need those items turned around faster as their aren't duplicates). The two would also, of course, help for parties. But the recommendations I read made me wonder if I'm off base with this thinking.
The kitchen is 20x16, the island is 4x10 (with seating in one end). If I didn't do the second dishwasher I would put drawers for prep items there instead of the dishwasher. I'd still have a narrower place for drawers and could put easy to reach up and grab lightweight stuff (salad spinners, colanders) on the upper shelves flanking the cooktop instead (directly behind the prep area). There also might be room in the lower drawers on the back wall where I am planning to put pots and pans (under cooktop and two 30 inch wide sets flanking the cooktop).
My initial thought was just a dishwasher drawer but I read reviews and I am not feeling great about them although it would save me storage space letting me keep a drawer under it. I have an existing Miele 24 inch stainless and I'd love to move to paneled in the new kitchen but hate to replace a functioning machine so I was going to reuse it. But if I went with two I could use the stainless in this more hidden back of the island location and get a new paneled for the main sink.
I am thinking of garbage pullout by both sinks.