I've heard over the years that these were made for the SeALs. However, I knew two SeALs in the 1980's, and after seeing the knife in some mall stores in around 1986, I asked the guys about them. One guy didn't have much experience with them, the other didn't really care for it at all. In his opinion, it was way too heavy, and absolutely mauled your hands if you did any serious cutting or chopping. Apparently, he thought the knife was designed to be used while wearing gloves. He said some folks in his platoon would carry them, but only because they were issued. (?) Not sure on that point. Most of the guys he knew at the time either carried a Ka-Bar, or something like it; if they carried hollow-handled knives, it was usually something like a Randall diving knife.
That's what I remember from years ago. There may be some SF folks lurking in the forums here who have more experience with it from that time frame.
I'd buy the knife if you want a nice momento from the 1980's "Rambo" era, but I wouldn't use it. There are other knives you can get today that would serve you just as well, and with the popularity of 'bug-out-packs' on other threads, I don't know that you'd really need the hollow handle anyway. That's just my opinion; I'm not into hollow handled knives myself.
thx - cpr