Magtech is pretty good stuff. Their Guardian Gold and First Defense lines are both good self defense rounds.
IMO their range ammo is more accurate than Blazer Brass by CCI, Wolf, PMC Bronze, and Winchester. It's usually more consistent round for round. I've had fewer problems with it than ammo from Remington, Winchester, Cor-Bon, or Hornady (in semi-auto pistol ammo only... I know Hornady the holy of holies to some - myself included - when it comes to rifle and revolver ammo). It's also somewhat cleaner shooting than most.
My best advice would be to buy it and try it. You may end up getting hooked.
"The best caliber and round for self defense are the ones in the gun closest to you" - My Grandfather