Question ROM + Kernel Version, NEOV

Hi,
Today i installed the newest version of legacy xperia with the latest dark kernel version,
But i reinstalled the old version of legacy xperia because the new has too much bug bug bug bugs :P
But i won't changed the kernel version, I let it on 20140518,
Actually im with 20140319 Legacy and 20140518 kernel and everythings works ok, better than with the 20140320 kernel, because with this one takes too much on start and the browser was not working correctly, with 20140320 on my phone sometimes takes 4 min or 5 on start the phone and 2 or 3 min on searching with android browser, with 20140518 works perfect the 2 and everythings works perfectly on the rom.
Can i let it or its better if i use the 0320 ?
My phone can get bricked?

Wifi was not working, but i solved it installing the wifi modules of 0518...

Can i let the 0518?

thanks and sorry for bad english, am i romanian <3