There is a post on here from one of the people involved in developing the Ecoegg
http://forums.moneysavingexpert.com/showthread.php?t=3450457&page=2
http://forums.moneysavingexpert.com/showthread.php?t=3450457&page=2
I'm still happy to use washballs 90% of the time, my whites aren't grey or smelly. No one in our family does a physical job that results in stains, smells and real grime. I'd rather spot treat anything with a spill on it, before it goes in the main wash. I use a net bag, but every type of washball can open in the machine ime so it doesn't bother me. If it does bother a buyer they can return them to Q as faulty even outside the 30 day MBG.