Same here - the total cost for a set is a little less than ordering from Mosaic directly, shipping costs and VAT added, and I don't have the hassle of picking the parcel up at the local customs office - when I order from Jazzmessengers it's a shipment within the EU. So far I ordered three sets from them, no problems, and they arrived within three days. Packing was excellent.
Never had any problems with ordering from Mosaic per surface mail, either. Some sets arrived after two weeks, some took six.