I have bought three of the tables and also the matching mats. The mats I've used at home as well as at the shop and I have not had a problem with them curling (I've probably gone through a half-dozen mats). The tables are just for use at the shop. We set them up, and leave them in place; we never move them around or fold & unfold them.
One has fallen apart unfixably; the others are all propped up with stuff under the casters (which tend to fall out); the one I use is about to fall apart. I was just crawling under it this morning trying to figure out what part has gone missing this time.
And - mind you - these are not our main cutting tables. Our big cutting table is actually a piece of plywood atop four identical double-wide three-drawer file cabinets. Very sturdy indeed! And the drawers are useful for holding pre-cuts. Our second cutting table is a very old but solid kitchen table up on blocks.
The tables from JoAnn's are affordable and space-saving but I have not found them to be durable.