Get about 1,000 gas on this thing (it will take around 13,000 ox) and then put everything else into movement speed, and you'll have just about the fastest living thing in the game. It actually effects how fast you fly too, and around 160 the only thing faster then you will be a skiff if you're a skilled enough flyer. Get one up to 200 or so and you'll never want to use another flyer for travel again. Anything else will just feel like it's moving in slow motion.
They can inflate and then they can do three things, do a huge jump that will deflate them, float/glide, and do a knockback attack that is similar to the diplodocus' only attack. They can also seat more than one person at a time