It does not seem to affect the handling on my boat, but it's only a 9.5 sb. Someone at AIRE told me that this design is meant to provide ballast, but it may also be a draining system as the zippered floor takes on water. I can say that I have yet to flip my little boat that should be very easy to flip. A lot of people comment on the positive aspects of the ballast as opposed to the excess weight.
The D series have a slick rounded floor, and this rocker makes it the best round boat IMO. At 13, 14 or 15 feet long, it is an amazing blend of stability and speed, and it turns very fast as well. I don't think the 130 is big enough to worry about it, but AIRE does make a sealed floor pocket now. I personally like the ballast floor and everyone I have talked to does as well. If I was in the market for a new round boat, I would without a doubt get a D series raft.