Okay, that video has some of the technical information in it so I will skip that part.
The term "easier to fly" is going to be different for ever person. Dual rate is going to limit the maximum throw of the servo whereas expo (or exponential) is going to alter how that travel happens at a given stick placement. If you are finding your flips and rolls are not fast enough, then you need to reduce the amount of dual rate you have in your Tx (get the number closer to 100 rather than 0). If you are finding the helicopter very twitchy when just hovering or making very small stick movements, then adding positive expo (NEVER add negative expo in a spektrum Tx, it will speed up the beginning throws) will help tame down that center stick movement or the "shaky hands syndrome".
As for numbers, I tell everyone to start out with 70% dual rate and +35% expo. Just be sure you have MAX throws before you set any DR/Expo. Once you have done all that, it is just time to go out and fly pack after pack and set it to what feels good for you. The settings I use you may hate and the settings the Matt (you or my admin lol) uses I may hate. It is a trial and error thing. But we will help any way we can.
