Over the last year or so we've bought three 14x12 national hives. One from Caddon, one from the M sale and from the T sale. Each hive includes an OMF, two supers and a crownboard. The latter two were a little cheaper and were described as seconds. All were made of Cedar.
We'd would rate the Caddon the best in terms of accuracy of cutting and quality of wood. The M one is pretty much as good, however there is a big knot on one panel and the roof isn't as deep. The T one is definitely the worst. The cutting is not as accurate, the two inner sides of the broodbox are a little bowed/warped so it was a real challenge getting them sit in the groves. The OMF floor doesn't have a proper ply inspection board, just a sheet of corex on plastic runners, the mesh is held in place with drawing pins and there's no entrance block provided!
The T hive is serviceable, I doubt it'll cause us any problems however it's not manufactured to the same quality as the other two. Of course with a sample of one from each company conclusions shouldn't be drawn, however I doubt we'll be buying another 2nds hive from T any time soon. Might get another from M in their sale at the end of the month though.