I have carried them since the 70's (before there was a thumb stud/spyderco hole).. I have always liked that I can open quickly with one hand, and while I was military I always carried one in place of my various issued automatics.....
Until I got to making a paycheck age, I probably went through 2 dozen cheap china knock offs.... they would never hold and edge, would not close properly (damaging the fine axe-like edge they would hold) and they would eventually fall apart.... When I got into the military and issued an automatic, I ordered a Balisong and have never looked back.... kind of like a Hi-point vs a S&W..... you really get what you pay for.....
Pay attention to what Doug M. said... there is much maligned thought about these "illegal" knives, just like "civilians cannot own machine guns" ... and just because you are carrying legally, or on the edge does not mean you will not be looked at with a lot of suspicion by some in authority.... don't push your luck....
Like carrying a gun, you get used to it, and after they meet me, most folks don't think twice about my pocketknife if they see it.... but I don't go on flashy-look-at-me-avoid-amputation shows either.... they can be (and in most cases should be) opened discreetly, used, and put away.... thats really the point... but in private.... yeah, they are a lot of fun
Also, as an aside, ANY of the newer spring assisted blades will be faster than a bali, and even a spyderco, or knife with a thumb stud will be just as fast if not faster, and you will not get the suspicious looks, comments, and hassle.... .02
If you still want one, get onto some knife forums and ask around, almost everyone has a few users that they will let go of for reasonable.... I would offer you my backup, but I lost it about a year ago, so I am down to one LOL....