Good pieces given as gifts from a sultan I doubt would not be of the same value as what the datu or sultan would wear.
As far as the asang-asang is concerned, yes they are made to be tight. However, as time progresses, organic materials shrink (also depending upon the change of climate into which they are found) and so I am not totally surprised that some parts of a kris might not be as tight as originally made. Also don't forget, some later owners (me included) might play with them now and again, and if not careful may loosen parts in handling. How many times have I repaired pieces that were played with by little boys and now need restoration?
Also the style of silver work I find consistent with Sulu workmanship, even to that time period. Shrinkage and cleaning may be factors here.
Finally, I agree with David in that the gunong in question is not lower in quality but in fact a great piece with that great silver chasing work (I love good bling!
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