While I'm pleased with the final result from this pergola, I cannot offer an enthusiastic endorsement of it. The kit is (mostly) designed and engineered well, but the materials were very unsatisfactory. There's a real problem with quality control at the site of manufacture (there doesn't appear to be any). As others have noted, wood pieces may be warped and/or twisted. After initial delivery, construction of my unit was delayed five weeks because of this. Most of the pieces originally shipped were unusable, and required replacement. Then the replacements needed to be replaced, and those did too -- even after I requested that replacement parts be inspected before shipment. A complete, usable set of parts required five separate shipments. I now have nearly enough lumber to build another pergola, except for the posts and some small parts. I finally just used the parts I had, even though some were still imperfect. Most were okay to use, but the long joists were still somewhat bowed -- which caused problems later. However, customer service was very polite and my requests were never questioned, although I was asked to send photos of the unusable parts. Replacements were delivered within three days.
Assembly is not especially difficult. The only bit that required two people was positioning the joists that create the square frame around the posts. The joist ends were most difficult -- holes were misaligned, and I had to re-drill them. This part of the design is cumbersome, and one wonders why the manufacturer didn't just make single lengths of board. Also problematic was attaching the slotted joists to the main joists. Because I had to build with parts that were bowed, the slots were out of alignment, requiring the use of a jigsaw.
When starting assembly, you should position the square plastic footers first (see the manual's basic setup dimensions) but be sure to consult the triangular dimensions on the next to last page. Step 13 instructs that entire structure must be moved into final position upon completion, but it's way too heavy and there's no good way to move it. If you measure correctly, you can assemble the pergola with the footers in place.
Some have suggested the wood is pine, but it's actually Chinese cedar (Cunninghamia lanceolata). It's evidently a species of cyprus, but supposedly still moisture- and insect-resistant. I should note also that the lumber is not sized in standard American thicknesses/widths (2x4s, 2x6s, etc). If you have a mind to replace any parts now or later, you'll have to do so from the distributor. However, if you have access to common power tools, you might be able to make do.
Generally speaking I'm happy with the result, but the process of getting to completion is not one I'd care to repeat. If you buy, be advised you may experience disappointment and frustration. I sent this review to the distributor, but they refused to post it. Go figure. Good luck!!!