UPDATE: I've noticed that the front door is difficult to get open/shut. It has to be forced. This isn't really a big deal, as we use the top door to stuff kitty in and that's really the important part. Getting her out isn't nearly as traumatic as getting her in is. When we need her to come out, we just yank a little harder on the door to get it open, and make sure it's latched before we stuff her back in the top. I assume it's just our particular one, not a line defect, and it's not really bothersome enough to return it.
______________________________________________________________________________________________________
We purchased this as a carrier for a second kitten. The product is easy to assemble and seems sturdy (though the kitten doesn't weigh much). The pieces are held together by multiple bolts with nuts covered by a nice plastic piece that allows you to tighten without using a tool. Extra nuts/bolts are provided.
This is a carrier best for a small cat-- I wouldn't want to try to cram our 17lb boy cat in there unless it was an emergency. But I have no doubt that (if we could squash him in) the carrier would hold up to his weight.
However, the tag does say it is for a pet that weighs 10lbs or less, so I wouldn't try making it his regular carrier (though the weight restriction might just be due to the fact that a larger animal would be uncomfortable in that small of a carrier.)
To conclude: good for smaller, normal weight cat. Probably ok in an emergency for tall/fat cats, but not as their regular carrier.