We've never spent that much on a dishwasher and got them at Lowes and Sears. I do think that Sears has better quality. If you had a bigger budget then I'd say go for the top of the lines but medium to lower styles will serve you well.
As for the dishes and having to do them before loading them that is all about your water temp. No dishwasher does a good job with luke warm water. If it's the hottest your hot water heater can make then they'll come out cleaner. How a person loads it will also have a huge impact on how it cleans. My husband will put pans on top of dishes then be upset with the pan isn't clean and the outside of the dishes are nasty from the pan.
If you do decide to increase your budget get a dishwasher with a built in water heater. They are closer to $500 though. But to me it's worth the extra cost because they just do better work.
I hate when we get a dishwasher and the racks rust out. That's an issue with the less expensive ones. The last dishwasher we bought had ceramic cover on the racks and it was still going great when we sold the house and moved.
A dishwasher that has a built in disposal is great too. I love that but it can still get clogged if chunks of food are left on the dishes.
Good luck! You might want to bide your time too, wait for an excellent sale and get a great dishwasher. They usually have big sales on appliances on national holidays.