"What is up with the Swiss Army brand? Why is it so great?"

The two Swiss Army brands are really just one company these days. They were separate companies hired by the Swiss army to manufacture their knives. Victorinox bought Wenger a while back.   They keep both brand names anyway.

The Swiss are a neutral country, but they still need an army for self-defense.  And the Swiss have inherited the German habit of doing things very well when they decide to do them.  The Vatican was so impressed with it that they have used Swiss mercenaries (not members the actual Swiss army) as bodyguards for centuries.  They wear silly uniforms and halberds, but they also carry guns.  (To my knowledge Victorinox is not making halberds with multiple blades for them.  Besides, the corkscrew would be kind of inconvenient hooked up to a ten-foot pole.)

The Swiss do still have an army.  In fact, they have a conscription: every Swiss male serves until he's 30.  After boot camp, most of them live civilian lives, but they have guns and ammo (and Swiss army knives, made by Victorinox and bearing the Swiss Army insignia) at home. 

But like I said, the Swiss are well known for being a serious people who make serious products.  Swiss watches are famous for being models of precision.  They've been supplanted by quartz timers, and these days Swiss watches are just for showing off the fact that you can afford a mechanical watch, but the Swiss fanaticism for quality control and precision is what make them possible at all (as well as expensive).

Victorinox gets to use the name Swiss Army even on products that they don't sell to the Swiss Army, by grant of the government (which knows a good deal when it sees one).  Only the products they actually sell to the Swiss Army carry the Swiss Coat of Arms.  Others carry the Victorinox or Wenger logos, which also incorporate the white cross but have different shield shapes (Victorinox a complex shield, Wenger a rounded square).

They keep their reputation by actually making pretty good products.  I'm fond of their Forschner brand of kitchen knives, which are a great value.  They're not the best knives, but they cost MUCH less than knives of comparable quality from German companies like Wusthof.