I have owned both a g10 harpuy and a karambit. They are both great kives, the karambit however is an acquired taste and features a very large handle. My hands are fairly small so it just didn't feel right for me no matter how much I willed it to. For cool factor and uniqueness get the karambit, for practical carry and use get the harpy. They are both of excellent quality and both of mine were razor sharp.
One more thing to consider with the karambit, it rides extremely high due to its clip placement. People might not know that you have a knife in your pocket but they may very well wonder what that big chunk of shiny steel with the ring thingy is. I wasn't comfortable at all carrying in my pocket but it did work well IWB. Also, Ves of vesleatherworks makes some awesome leather sheaths for the spydie karambit as well as many other models.
both of course is always the safest course;-)>
