Seems sound.   Assembly instructions poor, but common sense allowed for one day assembly (2 people - 6 hours).  Probably a shorter than 15' shed would be better, but we needed the length.  Long side walls bow slightly if something is leaned against them.  We reinforced 15' sides with a piece of angle iron attached at intervals along wall to prevent bowing and possibly rupture of wall seams.  



Pros: Maintenance free, seems durable, 
Cons: some predrilled holes stripped.  Took a lot of umph and torque to line up pieces, especially the final two wall sections.