I've done 23# of grain in my biab setup. No pulleys, no ladders, no hooks, just my scrawny arms and a clean bin next to the kettle. I lift the bag out and twist it as tight as I can for as long as I can hold it then it goes into the bin where I squeeze the rest out. In the case of that beer, I didn't squeeze a ton out since it would be the 2nd runnings for a partigyle. The weight aspect of biab is often way overstated.
My bag is the voille material that I double stitched on two sides, no signs of seam issues and I've done a dozen or so brews in the bag.