Dead Space 3 demo, Addendum

I just realized I forgot to make one major point which was the parts based crafting system.  They've touted the hell out of it and it's not as confusing as I was worried it would be.  It's generally pretty sensible and is just customizable enough to be unique and cool.  I'm sure it will be a bit more daunting in practice when they don't front load you with a lot of resources but it makes a lot more sense than the blue print/store system from earlier games.  I had always wondered in that situation 1)  Why they would even sell vital supplies like health, air, guns, ammo, armor on a ship like the Ishimura and 2) What's to prevent Isaac, with his engineering prowess, from hacking the freaking things to give him free shit?  Needing a certain part removes these because now you're not buying what you need from a store, you're really building it and improvising a weapon using parts and a work-bench.  It's kindof cool.