I would be very cautious about shipping things ahead to Argentina. They have very strict import rules and duties, and you could easily run afoul of them.
On the two previous Antarctic trips we shipped several Epson printers down, and even though we tried to arranged to leave them afterward as charitable donations to local schools we ended up having to pay duty.
The other problem, is where to ship things? I would be very nervous about shipping to a hotel ahead of time, in fact more so than checking an extra bag.
My suggestion is that if you have to bring a lot of stuff on a trip like this put it in a well protected case (like a Pelican) and then put that inside an old duffle bag. That way it doesn't screem "expensive stuff inside".
Though we all have heard, and have our own horror stories about lost and delayed luggage, the odds are about 98% that your bags will arrive just fine.
Michael