I don't know if Sonny, of Valiant, is still marketing the Gus swords built the same way as they were in the initial productions. There had been the initial production swords through Valiant which had a threaded section welded onto the tang. That, in itself, can be done well or badly. We see that with the Lutel swords but that is a channeled trough for the rod to seat in and superior welding. What I was seeing on the Valiant tangs in the beginning showed no markers that those had been as neatly done as the Lutel routine.
What failures I have read of concerning the Gus designed Valiant production swords has typically been over-tightening a very small fastener. Even in the old days of smooth nuts on Gus swords, there had been occasionally strong-armed failures. In that case more often the thread shoulder bottoming on the nut (not enough thread) or folk stripping the threads in the nuts themselves. Now that the swords come with a 5mm allen L wrench, it is really easy for any novice to over-tighten those soft threaded extensions. Then, there are going to be monkeys putting a socket drive allen in there and torquing until it snaps off (the threads typically).
My XIIIa from the first runs Gus did and my 1319 XIIa from the 2004 days both came with smooth nuts. Although I have slowed down a bit over the past few years, both these swords saw a lot of use with really minimal need to tighten them from snug. A couple/three times including dismounting once. Snug but not killed. I believe the Gus standard was, is 1/4x20 thread but the overseas Valiant production may be a smidge narrower (which just makes it easier for gorillas to kill them).
The hex drive nuts came along on Gus' stuff at about then 2004ish (fencing supplies if I have the right source in the beginning). One reason (and again iirc) Gus had originally used smooth nuts was to help folk not kill them. The later batches of Valiant may be uni-build tangs but even if not, as long sa the weld and threaded section are done right, then not abused, they should work fine.
Most compression fit swords I have ever had (a bunch) have settled a little in time. My two Gus swords were no exceptions and as mentioned never really need more than snugging them up a couple of times. Some are using Loc-tite and those using the hard stuff will regret that later. A dab of nail polish or super glue would work as well. As it is, I have never used goop on my Gus swords. Epoxy inside a Hanwei? Yes I have. What I have seen of the Valiant production Gus swords look as good or better for the price of anything else out there. Nope, I own none but would put them at the head of most lists of that price bracket and sword types.
Cheers
GC
