I've tried everything out there and Cascade Complete powder definitely is the clear winner. The Action Paks with Dawn in them work well for me, too, although they do tend to get a little too sudsy for my liking. The Electrosol with Jet Dry ball doesn't rinse well in my water. I haven't used Cascade Complete liquid but I have tried Sunlight and Electrosol liquids and they performed poorly. Plus, the liquid dishwasher detergents are bad for the machine.
When I lived in southern Florida, I used to keep my box of Cascade in a big zip lock bag and that eliminated the hardening problem. I read an article recently that said (regardless of where you live) to not buy more than what you'll use in a month. I forget the particulars but something in dishwasher powder breaks down with age rendering it less effective.
My mom swears by the Wal-Mart brand but I have noticed that her dishes don't get as clean as mine. She has a just-under-TOL Whirlpool (non-tall tub) and I have a very MOL Kenmore.
As for racking, why is it that people seem so inclined to want to "spike" their glassware in the top rack, meaning placing glasses and cups over the tines instead of using them as row separators? I know friends think I am hopelessly anal when I go behind them to rearrange in order to maximize space. It seems like a common sense thing to me, but "spiking" seems to be very popular....