This was easy to assemble, retains humidity nicely, and looks pretty good. It also keeps our cats out, even the one who likes to eat plants. The contents are completely visible and easy to access.
I left out the top and third shelves to have room for taller plants (I did keep the third shelf's center support bar in, for stability; it might do fine without that, but I didn't want to chance it). The greenhouse plastic doesn't cover the bottom, so I set it on an old, folded plastic dropcloth to protect the floor and have had no trouble.
EDITED TO ADD: I've since gotten a second one of these, and once again left out the top and third shelves. This time, though, I left out the third shelf's center support bar. It's perfectly stable, even with two heavy pots on the now-uppermost shelf.
EDITED AGAIN TO ADD: From reading the other reviews on here, it sounds like what I received (directly from Neptune both times, through eBay) is different from what some other people have received. Mine are sturdy, hold heavy pots with ease, and neither came with nor need zip ties. I wouldn't call them industrial-strength, and I use them indoors and would want to anchor them if I had them out in the wind, but mine aren't flimsy.