Consumer Reports rates Cascade higher, but in my experience, Finish Powerball 3-in-1 Tabs
(formerly Electrasol) work best for thoroughly cleaning dishes without clouding or etching glasses.  Neither of us have tested the new Finish Quantum –  it hasn't arrived yet in my local local stores or online, but you can print out a coupon for it and check it out as soon as it arrives.  Whatever dishwasher detergent you use, here are a few tips for better cleaning performance:

• You don't need to pre-rinse your dishes.  Enzyme-based cleaners like Finish dissolve the food residue, and you'll save lots of effort, time and water by not rinsing (or washing, as my balabusta grandmother used to do) the dishes before they go in the dishwasher.
• Load the dishes with the dirty side facing inward towards the jets. 
• Run the hot water in your sink until it gets hot before starting your dishwasher.  That way, the cold water sitting in your hot water pipes will go down the drain instead of filling your your dishwasher.  This will greatly improve your dishwasher's cleaning performance.
• Never, ever, ever use regular dishwashing liquid in your dishwasher.  The sudsing action can cause flooding and damage to the machine.
• Open your dishwasher soon after the cycle completes to let out some steam and speed drying.