I have a old NAA .32 acp Guardian, when I say old I'm meaning one of the original models (serial#AA53XX) with out a few of the newer models nicer touches.  My Guardian has the small, thin, and plain(no hash marks to help grip) takedown button, a smooth mag release button, with a couple of other slight differences on the internals ( hammer pin without clip, trigger bar spring shape) but all in all the same gun inside and out. The one thing I like that the newer guns do not have, is SS metal floor plate for the two mags.  All new guns and mag have thick plastic floor plate, I'll stick with the old floor plate, their thinner and make gun hight that much less.  I bring this up because I'm thinking about sending my .32 back for updates, which North American Arms will do for free ( not including shipment $50) on any of their firearms.  I am hesitant because my sweeting shooting little .32 Guardian has been perfect since I figured out what ammo it likes.  I had a couple of bobbles with some short O.A.L. JHP's in the beginning.  I now carry and shoot Hornady XTP or Fiocchi loaded with XTP, it's been %100 since.  I keep thinking, should I risk sending in a reliable CCW gun, only to get it back and have a problem or wait until I have a problem then send it in.  I guess either way I can't complain about a 15 year old pocket gun that has served me and my family well.  I think after 15 years it has earned a trip back home.....not yet I would miss it too much.