Pros:
They're kick-ass knives.
Cons:
I don't have enough money to buy two of everything.
But seriously...
The 5 is a hardcore SERE type knife, which is what I wanted it for and the reason I bought it. It's as versatile in duh wuhdz as it would be if TS ever HTF and I had to do a little urban scrounging. That baby doll is a beast. It's an ingenious design, the very picture of form following function. "Well made" doesn't even begin to do it justice. You can tell you're holding something meant for busting your way out of a downed aircraft the very first time you pick it up. It's got heft, man. The saber grind that looks like it might be a hindrance to some of these woods monkies, is actually not too bad. It acts like its own wedge when you baton it.
Downside is that you sacrifice a little bit of everything for it's Jack-of-all-trades design, and that's about all I can find wrong with it. It's a wonderful knife though. The saber grind does cause a slight bit of drag-- though that could be the coating, too. Chopping with it can be tedious, but choking back on the handle with a lanyard and/or using a baton with it takes care of that easily enough. The 1/4", weight forward balance of the blade helps it to be a quick and dirty chopper (though I'm sure the 6 will beat it handily in that respect) I can't say enough good things about it.
My nephew is talking about going into the Army...if he does, I'll probably give it to him to take as a service knife. Something I know he can count on to save his life if he needs it.
I can't tell you shit about the 6 though.