kvheli

hello everyone,
i am new to RC and i've been fly helis for about 2 months. i first start of with a helimax axe 100cp learned to hover and do some forward flights.
gradually move up to trex 450 pro, kds 450sd and hdx500.

i had made some mod changes to my 450 pro:
extend the boom using 450 dominator tail boom and torque tube
using align 360 cf blades
body kit from 480 devil fast

and now change flybar to fbl...

everything is align stock: motor, esc, servos..
using a futaba 401 gyro... i've been flying without a fbl gyro and doing hovering and some forward flights.

it's just very sensitive and twitchy with the sticks and unpredictable! it's such a nice bird and don't want to crash it (knock on wood)
would you recommend getting a fbl gyro or just keep it the way it is? the bird fly ok without it. but i am not comfortable doing any flips, rolls, etc.

my kds 450sd is a fbl and flies well... very stable but the movements is way more soft than my 450 pro. i feel comfortable with it. is it because align 450 pro servos have a much more movement than kds n300 servos?

any advice is appreciated. thank you.