My favorite 3-4" fixed blade is my gryptoillian...

Ok, it's a folder, and I'm sure if I tried very hard I could break it. But I'd put it up with many of the fixed blades on durability, the lock is that strong. It'd take a full tang to beat it.

The esse 3 and 4 have a thinner blade than the 5, if I recall. And are accordingly a bit lighter.