RE: Primer
This is a good primer as far as spray can stuff goes but it can't replace catalyzed primers such as K-36 especially for large areas. I use the SEM on occasion mainly for small parts or touch ups. Also the durability is not nearly the same. Paint adhesion is not as good and will be more prone to chipping. Still in terms of convenience, works pretty good, just remember to give sufficient time between coats.
Chris