I just got burned by this. The sender selected SurePost and UPS got the package here -- but USPS delivered it to the wrong house. Homeowner was mystified and I spent 24 hours tracking it down. UPS won't help you -- their I-800 # says they've having "extreme call volume" then hangs up on you. USPS won't pick up the phone... a trip to the main post office produces a number for the carrier annex, where someone eventually finds the carrier, who may remember where he left your stuff.

This is the price of cheap shipping -- it may get there just fine (this one was 4 days later than expected), but don't expect any help from either company if things go wrong. Just a word to the wise. Also, UPS can't track SurePost once it's turned over to the USPS.

(To answer another user in this thread -- the problem is that the USPS already *is* steadily going out of business... they're in a death spiral in 2013, so their service level keeps dropping. They're doomed, but for now we're stuck with this...)