What did you buy? And how hot is your hot water heat set to? What detergent are you using? A lot of things have changed in the last few years when it comes to detergents, and even DW's that formerly cleaned just fine can have issues. Or, if your DW wasn't installed with a high loop, the dirty water just drains back into your DW.

Bosch, Kitchenaid, and Meile get pretty uniform good reviews with every once in a while someone getting a lemon. If you're spending 1K and up in one of those brands, you should get a pretty good experience with the right detergent and water heater setting. As long as you don't have hard water, that is.

If you do live in Philly, then Philadelphia has moderately hard water and you are a perfect candidate for a Bosch 800 Plus with built-in water softer or better yet a Miele with built-in automatically adjusting water softener.

I'm beg. to think that it's a crapshoot, whether an appliance works great or not. I inherited a KitchenAid when I bought my house years ago. When it broke, I expected to replace it w/another KitchenAid, since that old one had lasted for years and until it broke, did an excellent job, while holding a TON of dishes. But for some reason that I no longer remember, I ended up buying a Maytag with extra insulation for quietness. I didn't think much of Maytag and thought I'd have to replace it in a few years. Surprisingly, that Maytag has had consistent excellent performance, with sparkling results, going on 15 years now without a single problem. Who'd have thought?

I have found that the dishes turn out the best with the gel detergent, as opposed to the powder. I also run the water at the sink until it's hot, so that the water into the DW is immediately hot, with no heatup involved (my old house has a long runup time until the hot water reaches the appliances). I do have a button to pre-heat the water, but I don't use it. I don't need to use the "pots & pans" button, either. I also just use the "normal" cycle. I keep the hot water heater at a standard temp (120 to 140, somewhere in there). One thing I don't like about the Maytag is that it doesn't hold as many items as the KitchenAid.

What I am MOST pleased about is that the extra insulation for quietness actually works, and I'm so glad I got that.

GREEN DESIGNS is on the right track, about two years ago the Feds made the dishwasher detergent companies drop phosphate from thier products. Phosphates kept the dirt from going back on your dishes so it is a must now that you use a rinse agent or a detergent that has a rinse agent in it like Cascade COMPLETE. This might solve your problem!