Flying with clubs twice a year — hard case or padded soft cover, and does the airline actually care?

I own both. The hard case is objectively safer and I use it maybe once a year, because it is heavy, it does not fold, and it lives in the way for 360 days. The padded soft cover with a support rod inside it — the rod that takes the crush load off the driver head — has done a dozen flights including connections without a single broken shaft, and it collapses into a cupboard. If your driver is the worry, the rod matters more than the shell.

Price the rental honestly before buying anything. Two trips a year at a resort rental rate for a few days can come to less than a good case plus the overweight fees plus dragging the thing through two connections. The counterargument is that you play worse with unfamiliar clubs, which is real, but if the trips are social rather than competitive it is worth doing the sum.

Weigh the whole thing packed before you commit, because that is where people get caught. A hard case is heavy empty, and once clubs, shoes and the towels everyone stuffs in there go in, you can be flirting with the standard checked bag limit and paying an overweight fee on both legs of every trip. A soft cover is a few kilos lighter empty, which is the entire margin. Most airlines these days treat a golf bag as a normal checked bag rather than special sports baggage, but the European carrier on your second trip may not, so check that specific airline's page before you book.

Mine got wet on a tarmac in a rainstorm and the soft cover soaked through into the grips and the bag itself, which took two days to dry and left everything smelling. Not a break, but not nothing. Whatever you buy, a bin liner over the clubs inside the cover costs nothing and solves it.