RE: Helisim RC help
Helicopters are really hard to figure out initially, when I first started I didn't ever think I'd be able able to actually control them and now I'm flying inverted circuits, piro flips, rotating tictocs etc. You'll get there, it all depends on how committed you are, how regularly you practice, and how much you push yourself. There's good info over in the Newbie and Flight School forums at helifreak, you should check them out.
I think I run about 20% expo on my trex500 3gx. My high rates are maybe 85 or 90% and low rates are like 70%, flying 3D. When people say to set pitch to 0 at mid stick they don't mean the value in the transmitter, they mean they actual pitch of the blades. CP helis are best flown in idle up mode at all time, meaning the throttle is at a constant speed (usually 90-100%), sometimes with a slight dip around mid stick to avoid overspeeding the blades when they're not under load. In this flight mode it's normal to have your mid stick position be 0 pitch, 12 degrees or so at high stick and -12 degrees at low stick.
Trex500 is a great choice for a first helicopter, it's MUCH better behaved and stable than a 450 size and will make learning the basics a bit easier. Check out Finless Bob's build videos for it over at Helifreak, should answer all of your questions. If it doesn't ask around in the other threads. Just take it one step at a time, don't get too far ahead of yourself and you should be able to get going fairly painlessly.
Oh my username on Helifreak is deca if you see me around :P