You get what you pay for. 
As other reviews state, the plastic washers are absolute garbage and I cant fathom why anyone thought they were a good idea. They break VERY easily. These plastic washers are used in places that you need a tight connection and its impossible to get without replacing these with your own metal ones. 
The frame itself is hard to get square and the swings will not swing straight unless the frame is perfect. 
The metal is sturdy and thick, the seats are high quality plastic and the see saw is a lot of fun. 
Overall this is a great purchase at this price, but heed the warnings and buy your washers BEFORE you start assembling the set