i dont missed shift that often but i do have a problem where when im raceing i dont look at my rpm's and i hit the rev limiter..better watch out or shes gonna go boom!!
depends on how often you use it, rule of thumb is about 10 runs now with the 150 you might get 8 runs out of it depends how much you purge and how long you run it. A run is considered like 15 second i believe. I always had them fill my bottle to 11 or sometimes 12 pounds.