For me it's been all over the place. Some items I'm shipping are arriving days before they are projected to, and others reach a certain location, and seem to sit for days before moving on. Doesn't seem to matter who the carrier is.....USPS or UPS. (those are the only carriers I use)
The experience Chris talked about with USPS.... I had similar, only with UPS. I had purchased two Burgmaster OB drill presses.....UPS literally destroyed both of them, and the fight was on (I had insured both packages). Fought for MONTHS, and never got a cent for the insurance claim. It's interesting how much you learn about an organization's customer service when there's $1K+ on the line.
One thing that has really been in my craw is Amazon. They took my money for a Prime membership, and the ONLY reason I paid for that membership, was the "2 day free shipping" as it was advertised then. I personally think they are using the Covid-19 thing as an excuse to save themselves tons of money on shipping, by not honoring the benefits they promised to Prime members. The last couple of item I've purchased that were marked "Prime", have taken 5-7 days to get to me. Frankly, since I feel like they've been shafting me, I tend to buy from other places, and often time get it much sooner then via Amazon. I doubt I'll be renewing my Prime membership.