A year or so ago, I sent a package Fed Ex via Mailboxes Etc. (note that MBE stores are actually independent franchises). When it didn't arrive the next day, I surfed to Fed Ex's site, entered the tracking number, and was shocked when Fed Ex's computer reported "no such number." I called the local MBE store the next day and they swore up and down that they'd submitted the package to Fed Ex just hours after I'd given it to them. They remembered it since it was a tube of rolled drawings -- kind of unusual. Fed Ex said, by phone, "We have no record of receiving it." So, I plotted new copies (it costed about eight dollars per page at the time to plot them making the drawing package in question worth about $200 in materials alone.) This time, I took my tube to the post office and paid their obscene overnight rate. The next day, the receipient called and said he'd received BOTH tubes. When I checked Fed Ex's site, it said that they'd received the package the previous day and delivered it normally. When I confronted MBE, they insisted again that they'd handed the package to Fed Ex several days earlier. After quite a bit of argument, they finally did agree to make an exception and refund my postage.
Remember, MBE stores are independently franchised. So, the quality of service you may experience at your local MBE may vary dramatically.