ekeller2,

  The oldest Hardi-board on my buildings is a shop with 4 x 8 sheets of stucco type grey finish.  Never painted or anything.  No change in 12 years.  Newest is our house with 8" lap siding, pre-painted.  Good at two years and expect it'll last longer than I will.  (I'm 68)  We love how it looks. 

  We couldn't get trim in the color we wanted so the trim pieces have Kilz2 as base, then two coats of whatever the best outdoor paint we can find.  Will see how long that paint lasts.

  From what I've seen, I plan to use it on everything here in south TX.  It takes the heat and direct sun better'n anything else I've ever found.  Easy to work with after you do it a while and learn what works and what doesn't.  I did buy a nibbler type cutter and love it.

Hope this helps.  Stetts