Hello! I ordered a semi customized DT5143 (2133 pommel and 2147 crossguard) and a DT2142 about 2 months ago and I wonder if there are some constructional differences that would affect their durability (I'm mean durability of the tang in the first place). I arranged a deal with the seller that I will take the one that will suit better to me. 2412 will be here by the Friday and 5143 sometimes later, and I would like to know which one could be more durable if I couldn't decide which one will I take due to the looks and the balance.

One more question, what do you think of Dt single handers tangs (and durability in general)? Sword of Galgano, st. Maurice of Vienna and 2121 12th century sword are also interesting and I might consider them.

Many Del Tin hand-and-a-half, longswords, and two handed swords use a welded tang (unless he's changed how he does things); some single-handers too. Before people clutch their chests and pass out, please keep in mind that a good weld and properly-sized parts don't have to be a weakness. While there have been scattered reports over the years of Del Tin's failing, they are the exception to the rule. And Lutel welds many of theirs and they don't have many reports of failures either. Done properly, a welded tang can be perfectly sound.

Del Tin durability is generally good, though you should expect hilts to loosen over time. The wood Fulvio uses for grips is soft and can be pretty prone to changes in humidity and temperature. So, expect to have to repeen the hilts from time to time.

Thank you for your answer, I'm aware of the loosening problem but a loose hilt is not a big problem to me, I was worried about the welding...

I agree with Chad, a well done weld can be strong (though personally I'd prefer it solid for peace of mind).
However, it may be worth it to check with Fulvio as to what his current manufacturing process is. I know that one of the last Del Tin's I have taken apart had a tang made out of the same stock as the blade......so they're not all of welded construction.....but then again ....it is a single hander and like Chad said I think the welds are particulary on the two-handed hilts. Then again, I believe Fulvio used to have welds on all his swords (even single handers).....so who knows.
Hope this helps,
Dan