What I appreciate with Sierras is that they're accurate, but a fmj wouldn't do a worse effect; perhaps it lacks some speed.
Here I hunt in very very brush area, but unfortunately not as remote and tremendous as you all! Most of time I shoot very close, but sometimes as far as 200 yards, and always on running boars.
The others hunters use more powerful cartridges, like 300wm or 9,3x74R, and shoot randomly. I think it's useless, I don't feel undergunned with my little 303".
Two years ago I used a 1892 Berthier mousquetoon, 8mm Lebel. Another very effective cartridge, unfortunately nowadays underrated.

Ps: I believe perretxiko's are in Spain!