Overall, I think this is a nice product, and the prices listed on the Plotter site are very fair. The A5 case on the site is listed at $22. That's right in line with similar products you might find from other brands, though the construction of this one is nicer than many I've used.
The only issues I had were the slightly-too-small size (I would like to be able to fit an A5 notebook inside), the fact that there's no way to keep it from snapping shut, and the unpleasant odor that comes with some PU leather. This one was particularly stinky, even after I propped it open with a pen stand to let it air out for a few days. I have a pretty sensitive nose, so it may not bother others as much as it bothered me. And it didn't bother me enough to stop me from eyeing the other sizes and colors available.
(This product was purchased from Plotter at the Chicago Pen Show.)