I've purchased 10 of these (4x2) to replace my previous wood raised beds (8x4). The 10 of these seem to have the same space as the 4 previous ones once you've accounted for the curved portions.
Decent quality, but manage your expectations. It was easy to assemble, I did it with a 1/4" impact driver and pliers for speed, but you could do it with a screwdriver. The rolled top edge isn't sharp, so it's safe. However, the corners and non-rolled edges will cut you quick.
Once assembled, the top portion at the corners where edges meet don't always align properly and often are not tight fitting because the bold is much lower than the top edge. To fix, I placed 1/8" pop rivets at the top to join the panels tightly. I used a hand sheet metal punch to make it easier. After that, I used tin snips and a file to bring any high spots down and smooth them out. Last, I place small bits around 4") of rubber u-channel with adhesive over the joints
It's a bit of extra work and materials, but I find it makes its much safer.