I recommend this product only if your area has extremely hard water and your washing machine tub with detergent scum and buildup. Otherwise, just use regular fabric softner. I did not see a major different result between Calgon Water Softener and a bottle of regular fabric softner, except the price.
I got a sample in the mail and I tryed it in the wash, it really does make a difference. The stains came out better with calgon then with laundry soap alone!