Personally, I don't care for the TDI series much. In forward grips, the angle of the handle limits the speed and power of a lot of techniques in kali, and renders other techniques unworkable without severe modification. Trapping and passing can both be problematic with short bladed knives with this kind of severe curvature, due to the fact that the wrist, when doing these motions, will lack stability and power. In reverse grip edge out it works pretty well, but, if I am going to use a knife with a curved handle in this type of grip, then I want a karambit--it does things the TDI can't do and has better retention. Oh, and before anyone asks, yes I have had these knives (I think I still have one of the large ones with a black coated blade and desert tan handle in the safe) and worked with them for quite a bit. I picked up one when Ka-Bar first came out with them because I got a huge law enforcement discount at a major law enforcement exposition that Ka-Bar attended and wanted to train with it a bit and see how it compared to some of my karambits.
Just my educated opinion. Your mileage may vary.
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