Neither is better in the abstract, and the honest answer depends on what you're optimising for. Flying buys you more time actually in Antarctica and skips the crossing, which matters enormously if you're a bad sailor or travelling with small children. Sailing costs less on average, opens up every itinerary we sell, and is far less likely to lose you trip days. When someone is torn, we lean sail, mostly because of the delay risk.
The comparison that usually decides it:
| Fly | Sail | |
|---|---|---|
| Crossing | About 2 hours each way | 1.5 to 2 days each way |
| Time on site | Roughly 5 to 9 days | Roughly 4 days on a standard voyage |
| Weather risk | Higher, delays are common | Lower and more predictable |
| Itineraries open | Very limited | All of them |
| Departure city | Punta Arenas, Chile | Ushuaia, Argentina |
Flying rules out South Georgia almost entirely. There are two or three very expensive trips a year that combine them, and you'd still sail the Scotia Sea, which isn't gentle. If South Georgia is on your list, that decision makes itself.