Linked thread deleted.
First off, congrats on the purchase! You'll love the RC18 series.
Give it a good, hard cleaning and see if the noise persists.
CC5400kV is a great start. Lots of power.
You don't need LiPo to run brushless; I run a 9200kV brushless off of a 1100mAh NiMH with plenty of speed, power and punch (obviously LiPo will give more, however).
Cheers,
Kyle.