Seems to be a decent, sturdy-ish pergola for the price, so far. A few pages of instructions were poorly drawn and could have been clearer (pay attention to the direction of the little triangle brackets 
that attach the roof beams). Product says that securing to a wall in back is optional -- we don't have the option to secure the back (against a neighboring building) and it definitely feels less sturdy as a result. Concerned about how it'll hold up without that attachment, but so far so good.