Bulgarian SandBag vs Weight Vest

I’m going to make myself a sandbag, mostly because it seems cheap and versatile, but I was wondering if anyone had any experience using them for loaded walks vs a weight vest.
By that I mean fireman style over the back of the neck, not farmers walks.

I’m pretty sure it will be uncomfortable, but that’s kind of the point of a loaded walk imo.
I had thought it might be a cheaper alternative to weight vest walking for beyond 531