RE: Power needed to open an Expandable?
There are a LOT of mistruths and rumors about mech b-heads. They have to be one of the most largely misunderstood products.
Firstly, you can NOT try to simply push most mechs through something by hand. Physics suggest that it just wouldn't be anything even remotely close to the act of shooting the same product into the same test medium. Tests have consistently proved that the Spitfire you mention is one of the fastest deploying mechs in the industry.... even in balistic jello.
Concerning the Rage heads, they seem to beno more than a fad. Remember the still available RM Snypers.... SAME thing! The Rage is simply marketed better,nearly a decade later. Just like the Snyper was,it came out and was all the "rage" and then died out in a couple years. I'd take a Rocket Steelhead over one ANY day. In fact, Petersons Bowhunting, as well as others, have conducted independant tests that have showed the Steelhead dominates in penetration even compared to fixed blade heads.
Regardless of your choice, make sure you shoot your b-head from a well tuned rig and you're going to have great performance. Good luck and good shootin'