We have an air trak and have ended up using it mostly for lower level gymnasts. Our air-trak is not like the one in the video posted above. It has about 20' of track that is at one level, then another ten that is at a lower level that looks like it could be a pit. Our preschoolers and beginning gymnasts love it. I also like teaching back handsprings off the higher end into the pit part (RO BHS this way, too). It gives the gymnast time to think about their body position from the time they leave their feet to the time that they land on their hands. Also, front handsprings and seat drops with the babies are great on the air-trak. Otherwise, we pretty much use it for fun. We take it whenever we go to open houses because we can let kids pretty safely jump down it, it's highly portable, and easy to clean. We tried taking it to some exhibitions, but the team girls don't really care for it and would rather do the mini-tramp.
In regard to the inflatable pit, I can't say that I care for it at first glance, but I would imagine that it sinks quite a bit when the gymnast hits it (I'm sure there's no bouncing involved). However, the sign that is pictured on the site does say "No diving" in capital letters, so the give must not be great enough to take big falls. As for noise, they also show the electric box that is used for it and I think that it may not be as loud as one would think. I wonder if it doesn't have air constantly pumped in -- that would mean no give, like a bounce house. It looks like the material has a LOT of room for movement. I bet that it's more like those blob things that you see at camps. It is always inflated with a set amount of air. When someone hits it, the give is proportionate to the amount of space there is for the air to move to another part of the pit. I don't know if that made any sense, but that's my idea of it when looking at the extra photos up close.