I have used them a lot, and the only hassle I ever had was when UPS claimed a parcel much bigger and heavier than it was. But Interparcel resolved it. I just needed to get a parcel rebooked today, and JamesG was very helpful. I sometimes use Parcels2Go, but they don't allow you to book the pickup time, whereas with Interparcel you can. My biggest issue with Interparcel seems to be they insist on you putting the postcode for the destination, but that is sometimes giving the wrong place. It is ok for the UK and the USA, but I have had problems in Germany and the Philipines, where the postcode did not correspond to the address I was given by the buyer. When I contacted one buyer, he basically said Interparcel had a very limited subset of the locations, and the location he gave me was correct. So I booked it with Parcels2go instead. But overall I am happy with Interparcel.