I own one, purchased at a time when I was really fascinated by big military-style fixed blades and considered the LMF2 to have an iconic look about it, right up there with the KA-BAR USMC, Ontario 499 and various others. I already owned a Gerber Prodigy at the time, and figured that the LMF2 must be better because it cost more. Well, when all is said and done, the Prodigy (or the newer Strongarm) is much more practical. The LMF2 is sort of a throwback in my eyes, not necessarily an outdated design, but not taking advantage of improvements in the industry. The sheath is actually more useful than the knife in my opinion, assuming that you are going into combat and need numerous carrying/mounting options. I suppose sticking with stainless steel has its advantages, but frankly, I don't know if it would be worth it to upgrade the 420HC to something else. Gerber already makes other knives with S30V, and KA-BAR has already gone the D2 with their "Extreme" model, but you're still talking about a big ol' knife that's not suited to most of the "real world" tasks most of us use knives for. I know some folks think that surviving the breakdown of modern society will call for such a knife, but if on a limited budget and with other, more critical items still needed, there are more practical options.
To be fair, Gerber hasn't really changed the LMF2 since . . . well, the LMF1, I suppose. I'm sure there are plenty of our troops wearing an LMF2 while on deployment, and I don't doubt that it can serve just fine at any number of tasks, right on up to combat if need be. However, as with the KA-BAR and Ontario I mentioned, it just isn't "the best" at anything, at least not compared to newer competitors. As far as I can tell, it all boils down to Gerber having successfully designed and built a knife that people think fills an essential role, not so different from all the outdoors enthusiasts convinced that they need some uber-bushcrafting knife to survive a day hike or an overnight stay in a campground.