Murali has a very good rep, I believe, but these are hand-made so each is different in its own right. Etching (with mustard, vinegar, FeCl, etc.) is sometimes used to see the hardened edge as it gets darker than the rest of the blade. Usual khukuris are only hardened on the sweet spot, starting about 1"-1.5" from the tip and extending for 3" or so depending on the length off the khukuri. Once the recurve starts (at the inflection point), the edge is pretty soft down to the cho. The spine and tang are everywhere soft for beter shock resistance (toughness). The differential hardening process has variable success and some edges are harder or softer than average. Every khuk must be given a workout by the user before it can be trusted for hardness and toughness (in the metallurgical sense of the words). HI's warranty is quite generous but not all models are created equal and thus are not covered for the same tasks equally (consult the lifetime warranty link given in the sticky with the links on this forum, and the safety link).
Hope this helps, sorry if I am not clear or if I misrepresent facts; I am sure tomorow someone will be better able to help. You've come to the right place for this kind of info.