I haven't used them in particular, but I just started using a Greenwash Laundry ball. It's supposed to change the ph levels in the water to release the dirt naturally, without detergent. I bought the ball for about $16 and it is supposed to last about 1000 washes. I've done 3 loads so far, including one white. The whites came out pretty good, but if there's ground in dirt or stains they recommend that you pretreat the spot with detergent to boost it.