I've had good luck with USPS. Usually 3 days max to get to me from anywhere in the country, and they'll deliver on Saturdays which UPS/FedEx won't. Not to mention it's usually the cheapest shipping option.
UPS, on the other hand, I sometimes get the feeling they intentionally delay their "ground" deliveries if they would otherwise get to me too quickly. Ordered something from within the same state, and it took 5 days to get to me. Zero tracking updates for a couple of those days, as if it just sat somewhere.
Another time, I ordered a computer to be shipped to me from Oregon. You know, the state right above mine. Instead, they went from Oregon, to Idaho, to Utah, to Nevada, and finally to California. You know, the way any smart person would...