Review on KitchenArt Professional Series 2 Cup Adjust-A-Cup: Premium Champagne Satin Adjustable Measuring Cup, 1/8 to 2-Cup Capacity by Caryn Adams

I've only used it a couple of times due to the awkwardness of moving the hub and it seems like cheap materials. I wonder if chemicals can be siphoned out of it? (yes, I know the ingredients only come into brief contact, but still...) It's difficult to clean: the oil/fat seems stuck (had to hand wash the casing when measuring the sour cream! and TWICE by hand when I measured the peanut oil) and water also leave marks. Unstable: If I measure more than 1.5 cups, the sleeve tilts and so I'm not sure about the measurement. On the plus side: lots of graduations, in both metric and English and conventional quantities (e.g. 1/2 cup is shown as "4 ounces" and "1/2 cup").