I have bought quite a few books from there and I have no complaints about the quality of the products. However, getting the books delivered is an awful experience. Usually, they do not provide any shipping details to the courier except for country (and sometimes name of the city, if they are feeling generous), so my order stays in the shipments distribution center and goes back because courier has neither delivery address, nor my contact information.
Sometimes, they send me an email to correct my shipping address (which was provided with shipping details anyway) on behalf of the courier. Anyway, it takes multiple tries because sometimes my reply just gets ignored / missed / lost / whatever and I have to send the same thing again a week or so later. Sometimes I get the books through regular post, but I am not sure how they decide which method of delivery to use (does not appear to be determined by size or weight of the item though).