Can anyone reassure me on these trampolines? Very good value, but would rather pay for a sky high if they are worth the extra... [[http://www.bigairtrampolines.com/catalog/all-trampolines-16/big-air-extreme-12ft-trampoline-safety-enclosure-2268.html?zenid=b8c55d407bd5c0edeefa74f62344169b Big air]]