I have been using them for a while but when I did cloth diapers I used something else for that (soap nuts are not really good for that).
I bought my last batch from greenvirginproduct.com. I have been happy w/them.
I mentionned that before but soap nuts are better in hot water. Since I wash in cold I boiled them and used the liquid from it. I save the nuts and make another batch when I have a lot of them and boil them a second time.
Only thing w/the liquid is that you can’t make too much ahead of time (it goes bad) and in summer time you need to put it in the fridge.