Is a tandem axle cargo trailer worth the extra $ over single

May I suggest MTI trailers as a quality, reasonably priced manufacturer.
I had to buy a little cargo trailer a couple years ago back in the Midwest and that brand stood out as the most economical...could been the dealer I suppose. But although I only owned it for about 2 weeks (1 way trip), it had quality features in a bare bones cargo trailer that many mid level brands don't. And had no issues with it loaded heavy, 1800 mile around the clock trip home at 80-90 mph!