We have had a 15' for a couple of years, but needed to order another due to the net being broken. This arrived quickly, was fairly easy to put together. The oval shape seems to be a little less tight as far as the actual bounce compared with the circle, but still a great product and doesn't affect the jumping unless a lot of people are on at one time, which the manufacturer warns shouldn't happen. Still, fully aware of the warning, all 5 of my children have been on at one time to stargaze and that is where we could see the bigger size sags a bit more than the smaller one. Overall, the kids love it and we would purchase again.  Pros: Quick shipping, easy assembly, large size Cons: Sags a bit more compared to a round, entrance seemed to be in a weird position, but that is how it was supposed to be, just not centered between bars.