I purchased a 14 ft by 16 ft rectangular trampoline from Adams Trampoline about 4 months ago. (
www.trampolineservices.com/). I went with a rectangular one because everything I read suggested rectangular trampolines had better bounce than round ones. The down side is they are more expensive and they are easier to get bounced off of if one lands off balance and too close to the springs. I got the 14 X 16 because it gave me a 12 x 14 ft mat. I am pushing 50 years-old and I am not as limber as I once was. I have gotten off balance while throwing tricks, but have yet to get bounced completely off the tramopline without having regained my balance enough to where I could step on the frame and then off onto the ground. I am really happy with my trampoline. It has helped me with new tricks and learning air awareness. Like most that have commented on trampolines, I can do more on it than I can on a wakeboard. But, I still think it has been a big help to me in learning to progress on the water. I think most people would agree that the bigger the mat size, the more comfort one has in throwing/learning new tricks. I learned a lot about tramoplines by reading other threads on this board and by looking at variuos companies websites. There are a couple of threads about trampolines in "trick tips" that may be of interest to you also. If one searches "tramoplines" on the Internet, there are numerous companies that sell them. I selected Adams because they were in my state. Turned out the manufacturer they distribute for was in Texas too. I could have bought it direct from the manufacturer for the same price. I also did an on-line search of the company I purchased from using a BBB website before buying the trampoline. I did not get the safety net because I do not have any kids and it added about $500 to the cost. My 14 x 16 tramopline ran $1500 delivered to my home. Round ones are certainly a good bit cheaper. Mat size was far more important to me than cost. That was why I went with the biggest rectangular one I could find. When deciding on what you want, recognize that the demensions of the trampolines most companies list in their adds is the frame size and not the mat size. Some companies do it by mat size, but most use frame size. Again, mat size was the biggest factor in making my selection. I am 6' 2" and weigh 195. Having a 12 x 14 ft mat gives me piece of mind when learning new tricks. When I was a kid, my family had a 12 x 8 tramopline. That would be a mat of about 10 x 6 ft. Had I gotten one that size, I would have been bounced off or landed in the springs several times already. I have my trampoline butted up against a tree in the yard. That is what I tie my rope and handle to. That is what little bit I know about them. Hope it helps.