I've restored antiques and generally they are great old pieces of machinery, but I tend to think that they are not as easy to use as new pieces of equipment.
Now if we look at a Chinese tractor, we are basically looking at newly produced old technology. Nothing fancy about them, just basic, almost rustic, workhorses.
Personally I would prefer to buy a tractor from someone who can get me parts, and can fix it. With an old tractor, that can be an iffy proposition. Ford 8Ns are easy to get any part for, so if you get one of those, you can get it fixed, even if you don't do the actual fixing. A Chinese tractor can be bought from one of several types of dealers. #1- Mail order. #2- Sales dealer, no parts/service. #3-Full service dealer. For me, I would only buy from a full service dealer. But if you are handy with a wrench, and know some basics, you might feel capable of fixing basic stuff.
Now, none of that actually answers your question. So to get to the answer, I guess I would opt for the Chinese tractor over the antique if I was actually doing some work with the machine. The new unit will have some safety features that the old iron wont have. The odds are the old unit will be a gas engine, I prefer diesel, which the Chinese tractor will have. Antique iron turns in a large radius, a new Chinese tractor will spin in a smaller circle. So I guess from a practical standpoint, I would opt for the Chinese tractor.
Now an 18hp Chinese tractor is pretty light in the hp department, and probably light in overall weight as well as being pretty small in size; for plowing snow I would certainly want 4 wheel drive. The lighter weight of the small Chinese unit will be at a serious disadvantage to the old tractor if it is only a 2 wheel drive model, so much of a disadvantage that it might not be worth using. The other issue to consider is the type of log splitter being used and if it requires a specific PTO hp to run a pump, or if it requires a hydraulic line so that may, or may not become an issue, but again that would depend on the splitter, and how it operates.