No, I prefer using USPS because I get much better service and results through USPS.
1) I just ordered a new saw from Bailey's on a Thursday. The saw shipped UPS. The following Sunday, I realized I needed a tool for the incoming saw, so I ordered that from Bailey's as well. The tool shipped USPS. USPS delivered the tool to me 2 days ago. Ordered on Sunday evening, delivered Tuesday afternoon Cali to Ohio. UPS isn't going to deliver the saw for another 5 days, making it over 10 days in transit from Cali to Ohio.
2) UPS and FedEx drivers suck here. Often mark a package as delivered but don't actually drop it off for another day or two. Both park on the road, walk in, toss package onto the cement in front of the door in plain view of the road regardless of weather. Don't ring the bell, don't knock, just vanish. Sometimes they don't even knock or ring before they stick the missed package notice on the door if I have to sign for it. USPS carrier will drive into the driveway because I've told him it'll set off the driveway alarm and then raise holy hell at the door when he drops stuff off even if I don't need to sign for it because I've told him that I'm often working in the shop in the back of the house with hearing protection on and can't hear a reasonable knock at the door. If the weather's bad, he always bags it and then puts it under or on something as required to keep it out of the weather. He never leaves stuff in plain sight of the road. He's actually forgotten something and then come back at the end of his shift to make sure I got it that day. If the weather's good and I'm out working when he tries to drop something off, he'll lay on the horn a few times until I come out of the woods to make sure he doesn't miss me. I'm not actually sure how he can tell when I'm outside, but he's never wrong so far.
3) I have the lowest rate of lost, damaged, or delayed packages when using USPS to ship to my customers.