As far as UPS, i think it depends on where you are located. I was a driver helper for them this last winter season, the driver I was with was F'n awesome, been on the same route for 20+ years. A few thing have changed ( I know because I grew up in my area), but he had it down. I also worked with a couple of other drivers and they even though they were newer, knew what they were doing. The center manager was on his game as well.
I personally do not ship UPS unless I need to. USPS more recent due to their flat-rate shipping (only domestic for me). I also used to work for FedEx and they have never done me wrong. Used to use them exclusively as I got a fatty discount. Do not get as good a discount now, so depends on the the parts/items I am sending.
As far as receiving packages, UPS has not done me wrong in my current place of residing. The FedEx drivers around here seem like they could use a few extra brain cells.