The first seat that I have infused. It does have a couple of foam ribs on the back making infusion an easier overall process than our usual method with vacuum. The disadvantage is than we end up using a bit more resin and have more materials that need to be throw any. The big plus is the potential weight saving. While this seat is a bit light for my liking I will test it some to see how it stands up. The weight I would be happy with is under 500g. This one weighs in at 414g without the holes in it but I would like to add a bit more carbon in a couple of spots.