nitro to brushless

[uarghhh]

hey guys... I'm alomost decide on motor/esc.. almost :) Just have a question (or two) For the esc, will buy castel mm

first : Feigao brushless motor 540 8xl or Feigao 540C 8XL Brushless Motors? Is that the same motor but with heatsink?

second : the feigao 10xl have a higher kv? not suppose to be the opposite? higher turn motor have less kv?

third : 2 pack of gp 3300.... maybe 7-8 minutes of run time? what do you think..... I'm a little affraid of li-po... my second choice is apogee li-mn but the don't do it in 4s...

thanks a lot guys.. you help is really appreciated