I'm happy to share my thoughts on a Sumo Omni that I recently reviewed. Unlike traditional bean bag chairs which offer just one basic shape, Sumo offers several ways to reshape the bag.
When flat Omni is like a 5'5 x 4'5in pillow and weighs around 18 pounds. All the different forms start off from this giant rectangular pillow. You have to use your creativity to come up with a seating that will work the best for you. The options to rotate, move beads around and squish the bag are limitless. I have to admit, initially, it was hard to come up with a comfortable shape - I couldn't decide if most of the beans should be on the base or on the back. For me, love the back support, which typical beanbags don't offer.
The material outside is made of rip-proof nylon and is filled with tiny polystyrene foam beads. There are enough beads in the bag to create a comfortable seating, but you could always buy more and add them inside. I've noticed that this material can be slightly slippery if the base is not heavy on a smooth flooring. It does not slip on a carpeted flooring.
Finally, I think these are perfect for children and adults to sit back and relax. It is also a good seating for office lounges. This style of seating will change the room's ambiance to a more relaxed and casual setting where one can totally unwind. I've even dozed off with my mac on my lap on this Omni! I've a picture for you and below that is from Sumo's website on various ways you could contour this beanbag.