I've had 3-4 shipping problems with UPS. Everything has always arrived on time with FedEx though. They get a thumbs up for me.
However if it's offered, I ship USPS Priority mail. It's cheaper and I always get stuff around the same time it would take FedEx. Priority is faster than UPS Ground anyway and a lot cheaper!
FedEX all the way I will never use UPS again if I can help it. The last 4 packages I recieved from them have looked as though they've been used for football practice.