I haven't painted my ES, (Hell, I haven't even started and won't until I get my 37' racing sailboat completed in the next 2-3 months) but I have 30+ years of experience in composites and building and painting boats.  What I plan on using is US Paint 545 primer for most of the base but may use some hi build if warranted.  The stuff sand great and is tough.  Then finish it with Awlgrip as I have with my last 4 boats.  Don't know about the primer you're talking about.

Dan Newland