One post cracked, three pickets dented.  Call manufacturer and they are sending replacements.  Definitely use a post pounder!  Every went well with the exception of drilling into the post.  That’s not an easy task without proper strength drill.  Direction are easy to follow and as long as you follow them, it’s pretty easy.  A little time consuming to ensure everything is level and spaced correctly but once done it is worth the effort.  I do have a slight slope but used a board across the top to ensure I was at same height.  Looks good and if a 60 year old lady can do this on her own, I’m pretty sure anyone can!