I ordered 4 wash mitts from Carwash'n'wax and the quality between them varied loads, I was only happy to use one out of the 4 that arrived. I try to stick to the actual Eurow branded ones only now as they seem to be a more consistant in there quality.
I like the SP ones no problems with them thinning when wet, the colour is not ideal as it makes things harder to spot in them.