First of all, welcome
Like many others here, I have used khuks with both the standard thru-tang as well as the full slab (chiruwa) tangs. IMHO, both are perfectly and equally fine for hard work and use. Keep in mind that there really isn't a huge difference in the amount of material that makes up each style of tang. The thru tangs, sometimes called a rat tail tang, is fully forged with the blade...not tacked on like many cheaper knives. Also, calling these tangs "rat tail" is a misnomer. They are more like kangaroo or crocodile tails

They are fat through the bolster and slowly taper as they get to the buttplate before they are peened over the keeper. In other words...super TOUGH!

Personally, I believe that the chiruwa style of tang is "stronger" in the sense that it gives the person using it a feeling of extra toughness. The only real advantage that I see to the chiruwa style over the standard thru tang is that the slabs could be readily repaired in the field. However, if you have ever tried to remove a standard Khuk handle with a thru tang, then you will know that getting the handle off the tang generally requires boiling water, fire, a file, a hammer, and tenacious resolve

They are peened over at the end and stuck fast through out the handle with laha (a type of natural epoxy that does not give up the ghost easily)

! Generally, I prefer the standard tang to the chiruwa tang just based on how they feel in hand. However, my YCS is a dream to use and has the chiruwa tang.
Finally, if you are thinking about getting an HI khuk, rest assured that Yangdu will stand behing her warranty 100%. If you should ever have a failure, just let her know and she will make it right. HI is a remarkable company in this regard...as well as just about every other regard, for that matter
Once again, welcome
Jake